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Provide tags and a correct Python 3 solution for this coding contest problem. One day Kefa found n baloons. For convenience, we denote color of i-th baloon as si — lowercase letter of the Latin alphabet. Also Kefa has k friends. Friend will be upset, If he get two baloons of the same color. Kefa want to give out all baloons to his friends. Help Kefa to find out, can he give out all his baloons, such that no one of his friens will be upset — print «YES», if he can, and «NO», otherwise. Note, that Kefa's friend will not upset, if he doesn't get baloons at all. Input The first line contains two integers n and k (1 ≤ n, k ≤ 100) — the number of baloons and friends. Next line contains string s — colors of baloons. Output Answer to the task — «YES» or «NO» in a single line. You can choose the case (lower or upper) for each letter arbitrary. Examples Input 4 2 aabb Output YES Input 6 3 aacaab Output NO Note In the first sample Kefa can give 1-st and 3-rd baloon to the first friend, and 2-nd and 4-th to the second. In the second sample Kefa needs to give to all his friends baloons of color a, but one baloon will stay, thats why answer is «NO».
instruction
0
4,718
6
9,436
Tags: brute force, implementation Correct Solution: ``` n,k = map(int, input().split()) s = input() r = [0]*26 y=0 for i in s: nomer = ord(i)-97 r[nomer] +=1 for i in range(len(r)): if r[i] >k and r[i] !=0: y+=1 if y>0: print('NO') elif y==0: print('YES') ```
output
1
4,718
6
9,437
Provide tags and a correct Python 3 solution for this coding contest problem. One day Kefa found n baloons. For convenience, we denote color of i-th baloon as si — lowercase letter of the Latin alphabet. Also Kefa has k friends. Friend will be upset, If he get two baloons of the same color. Kefa want to give out all baloons to his friends. Help Kefa to find out, can he give out all his baloons, such that no one of his friens will be upset — print «YES», if he can, and «NO», otherwise. Note, that Kefa's friend will not upset, if he doesn't get baloons at all. Input The first line contains two integers n and k (1 ≤ n, k ≤ 100) — the number of baloons and friends. Next line contains string s — colors of baloons. Output Answer to the task — «YES» or «NO» in a single line. You can choose the case (lower or upper) for each letter arbitrary. Examples Input 4 2 aabb Output YES Input 6 3 aacaab Output NO Note In the first sample Kefa can give 1-st and 3-rd baloon to the first friend, and 2-nd and 4-th to the second. In the second sample Kefa needs to give to all his friends baloons of color a, but one baloon will stay, thats why answer is «NO».
instruction
0
4,719
6
9,438
Tags: brute force, implementation Correct Solution: ``` n, k = map(int, input().split()) b = list(input()) a = {} s = 0 for i in b: a[i] = a.get(i, 0) + 1 for i in a: if a[i] > s: s = a[i] if s > k: print('NO') else: print('YES') ```
output
1
4,719
6
9,439
Provide tags and a correct Python 3 solution for this coding contest problem. One day Kefa found n baloons. For convenience, we denote color of i-th baloon as si — lowercase letter of the Latin alphabet. Also Kefa has k friends. Friend will be upset, If he get two baloons of the same color. Kefa want to give out all baloons to his friends. Help Kefa to find out, can he give out all his baloons, such that no one of his friens will be upset — print «YES», if he can, and «NO», otherwise. Note, that Kefa's friend will not upset, if he doesn't get baloons at all. Input The first line contains two integers n and k (1 ≤ n, k ≤ 100) — the number of baloons and friends. Next line contains string s — colors of baloons. Output Answer to the task — «YES» or «NO» in a single line. You can choose the case (lower or upper) for each letter arbitrary. Examples Input 4 2 aabb Output YES Input 6 3 aacaab Output NO Note In the first sample Kefa can give 1-st and 3-rd baloon to the first friend, and 2-nd and 4-th to the second. In the second sample Kefa needs to give to all his friends baloons of color a, but one baloon will stay, thats why answer is «NO».
instruction
0
4,720
6
9,440
Tags: brute force, implementation Correct Solution: ``` n, k = map(int, input().split()) s = input() l = set(list(s)) a = [s.count(i) for i in l] if max(a) > k: print('NO') else: print('YES') ```
output
1
4,720
6
9,441
Provide tags and a correct Python 3 solution for this coding contest problem. One day Kefa found n baloons. For convenience, we denote color of i-th baloon as si — lowercase letter of the Latin alphabet. Also Kefa has k friends. Friend will be upset, If he get two baloons of the same color. Kefa want to give out all baloons to his friends. Help Kefa to find out, can he give out all his baloons, such that no one of his friens will be upset — print «YES», if he can, and «NO», otherwise. Note, that Kefa's friend will not upset, if he doesn't get baloons at all. Input The first line contains two integers n and k (1 ≤ n, k ≤ 100) — the number of baloons and friends. Next line contains string s — colors of baloons. Output Answer to the task — «YES» or «NO» in a single line. You can choose the case (lower or upper) for each letter arbitrary. Examples Input 4 2 aabb Output YES Input 6 3 aacaab Output NO Note In the first sample Kefa can give 1-st and 3-rd baloon to the first friend, and 2-nd and 4-th to the second. In the second sample Kefa needs to give to all his friends baloons of color a, but one baloon will stay, thats why answer is «NO».
instruction
0
4,721
6
9,442
Tags: brute force, implementation Correct Solution: ``` n,k=map(int,input().split()) a=input() d={} for i in a: d[i]=d.get(i,0)+1 for i in d: if d[i]>k: print('NO') break else: print('YES') # n,k=map(int,input().split()) # a=input() # d={} # kol=0 # kolkol=0 # for i in a: # d[i]=d.get(i,0)+1 # print(d) # for i in d: # if d[i]%k==0: # kol+=1 # for i in d: # if d[i]==1: # kolkol+=1 # if kol==k or kolkol==len(d): # print('YES') # else: # print('NO') ```
output
1
4,721
6
9,443
Provide tags and a correct Python 3 solution for this coding contest problem. One day Kefa found n baloons. For convenience, we denote color of i-th baloon as si — lowercase letter of the Latin alphabet. Also Kefa has k friends. Friend will be upset, If he get two baloons of the same color. Kefa want to give out all baloons to his friends. Help Kefa to find out, can he give out all his baloons, such that no one of his friens will be upset — print «YES», if he can, and «NO», otherwise. Note, that Kefa's friend will not upset, if he doesn't get baloons at all. Input The first line contains two integers n and k (1 ≤ n, k ≤ 100) — the number of baloons and friends. Next line contains string s — colors of baloons. Output Answer to the task — «YES» or «NO» in a single line. You can choose the case (lower or upper) for each letter arbitrary. Examples Input 4 2 aabb Output YES Input 6 3 aacaab Output NO Note In the first sample Kefa can give 1-st and 3-rd baloon to the first friend, and 2-nd and 4-th to the second. In the second sample Kefa needs to give to all his friends baloons of color a, but one baloon will stay, thats why answer is «NO».
instruction
0
4,722
6
9,444
Tags: brute force, implementation Correct Solution: ``` n, k = list(map(int, input().split())) s = list(input()) unique = set(s) count = {} for i in s: count[i] = count.get(i, 0) + 1 values = [count[c] for c in unique] values.sort(reverse=True) assign = [[] for i in range(k)] each = n//k rem = n%k for i in range(k): for j in range(each): for v in range(len(values)): if(values[v] > 0 and v not in assign[i]): assign[i].append(v) values[v] -= 1 break for v in range(len(values)): while(values[v] > 0): got = False for i in range(k): if(v not in assign[i]): assign[i].append(v) values[v] -= 1 got = True break if(got == False): break #print(assign, values) ans = True for v in range(len(values)): if(values[v] > 0): ans = False break if(ans == True): print('YES') else: print('NO') ```
output
1
4,722
6
9,445
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
instruction
0
5,220
6
10,440
Tags: implementation Correct Solution: ``` def rhyme(a,b,k): v=["a","e","i","o","u"] i_a=None i_b=None v_a=0 v_b=0 for i in range(len(a)-1,-1,-1): if a[i] in v: v_a+=1 if v_a==k: i_a=i break for i in range(len(b)-1,-1,-1): if b[i] in v: v_b+=1 if v_b==k: i_b=i break if i_a!=None and i_b != None and a[i_a:]==b[i_b:]: return True return False def main(arr,k): style={0:"aabb",1:"abab",2:"abba",3:'aaaa'} ans=[] for j in range(4): c=True for i in range(len(arr)): q=arr[i] if j==0: if rhyme(q[0],q[1],k) and rhyme(q[2],q[3],k): continue else: c=False break if j==1: if rhyme(q[0],q[2],k) and rhyme(q[1],q[3],k): continue else: c=False break if j==2: if rhyme(q[0],q[3],k) and rhyme(q[1],q[2],k): continue else: c=False break if j==3: if rhyme(q[0],q[1],k) and rhyme(q[1],q[2],k) and rhyme(q[2],q[3],k): continue else: c=False break if c: ans.append(j) if 3 in ans: return style[3] elif len(ans)>=1: return style[ans[0]] else: return "NO" n,k=list(map(int,input().split())) arr=[] for i in range(n): temp=[] for j in range(4): temp.append(input()) arr.append(temp) print(main(arr,k)) ```
output
1
5,220
6
10,441
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
instruction
0
5,221
6
10,442
Tags: implementation Correct Solution: ``` #from bisect import bisect_left as bl #c++ lowerbound bl(array,element) #from bisect import bisect_right as br #c++ upperbound br(array,element) #from __future__ import print_function, division #while using python2 # from itertools import accumulate # from collections import defaultdict, Counter def modinv(n,p): return pow(n,p-2,p) def get_suffix(s, k): vovels = "aeiou" for i in range(len(s)-1, -1, -1): if s[i] in vovels: k -= 1 if k == 0: return s[i:] return -1 # aaaa = 1 # aabb = 2 # abab = 3 # abba = 4 # none = -1 def get_scheme(s1, s2, s3, s4): if s1 == s2 == s3 == s4: return 1 if s1 == s2 and s3 == s4: return 2 if s1 == s3 and s2 == s4: return 3 if s1 == s4 and s2 == s3: return 4 return -1 def get_scheme2(x): if x == 1: return "aaaa" if x == 2: return "aabb" if x == 3: return "abab" if x == 4: return "abba" def main(): #sys.stdin = open('input.txt', 'r') #sys.stdout = open('output.txt', 'w') # print(get_suffix("commit", 3)) n, k = [int(x) for x in input().split()] rhymes = [] no_scheme = False for i in range(n): s1 = get_suffix(input(), k) s2 = get_suffix(input(), k) s3 = get_suffix(input(), k) s4 = get_suffix(input(), k) if s1 == -1 or s2 == -1 or s3 == -1 or s4 == -1: rhymes.append(-1) else: rhymes.append(get_scheme(s1, s2, s3, s4)) # print(*rhymes) rhymes = set(rhymes) scheme = "" if -1 in rhymes: scheme = "NO" elif len(rhymes) == 1: scheme = get_scheme2(rhymes.pop()) elif len(rhymes) == 2 and 1 in rhymes: rhymes.remove(1) scheme = get_scheme2(rhymes.pop()) else: scheme = "NO" print(scheme) #------------------ Python 2 and 3 footer by Pajenegod and c1729----------------------------------------- py2 = round(0.5) if py2: from future_builtins import ascii, filter, hex, map, oct, zip range = xrange import os, sys from io import IOBase, BytesIO BUFSIZE = 8192 class FastIO(BytesIO): newlines = 0 def __init__(self, file): self._file = file self._fd = file.fileno() self.writable = "x" in file.mode or "w" in file.mode self.write = super(FastIO, self).write if self.writable else None def _fill(self): s = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.seek((self.tell(), self.seek(0,2), super(FastIO, self).write(s))[0]) return s def read(self): while self._fill(): pass return super(FastIO,self).read() def readline(self): while self.newlines == 0: s = self._fill(); self.newlines = s.count(b"\n") + (not s) self.newlines -= 1 return super(FastIO, self).readline() def flush(self): if self.writable: os.write(self._fd, self.getvalue()) self.truncate(0), self.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable if py2: self.write = self.buffer.write self.read = self.buffer.read self.readline = self.buffer.readline else: self.write = lambda s:self.buffer.write(s.encode('ascii')) self.read = lambda:self.buffer.read().decode('ascii') self.readline = lambda:self.buffer.readline().decode('ascii') sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip('\r\n') if __name__ == '__main__': main() ```
output
1
5,221
6
10,443
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
instruction
0
5,222
6
10,444
Tags: implementation Correct Solution: ``` n,k = map(int,input().split()) lis=[] vov=['a','e','i','o','u'] d={} d['aabb']=d['abab']=d['abba']=d['aaaa']=0 for i in range(n*4): s = input() lis.append(s) if i%4==3: tmp=['']*4 for j in range(4): s=lis[j] c=0 cou=0 for ll in s[::-1]: cou+=1 if ll in vov: c+=1 if c==k: tmp[j]=s[-cou:] break # print(tmp) tt=1 if tmp[0]==tmp[1]==tmp[2]==tmp[3] and tmp[0]!='': d['aaaa']+=1 tt=0 if tmp[0]==tmp[1] and tmp[2]==tmp[3] and tmp[1]!=tmp[3] and tmp[1]!='' and tmp[3]!='': d['aabb']+=1 tt=0 elif tmp[0]==tmp[2] and tmp[1]==tmp[3] and tmp[1]!=tmp[0] and tmp[1]!='' and tmp[0]!='': d['abab']+=1 tt=0 elif tmp[0]==tmp[3] and tmp[1]==tmp[2] and tmp[2]!=tmp[0] and tmp[1]!='' and tmp[3]!='': d['abba']+=1 tt=0 if tt: print("NO") exit() lis=[] c=0 for i in d: if d[i]>0: c+=1 if c==1: for i in d: if d[i]>0: print(i) exit() elif c==2 and d['aaaa']>0: for i in d: if d[i]>0: print(i) exit() else: print("NO") ```
output
1
5,222
6
10,445
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
instruction
0
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Tags: implementation Correct Solution: ``` n, k = map(int, input().split()) ve = 'aeiou' abba, aabb, abab = 1, 1, 1 for j in range(n): a = ['']*4 for i in range(4): a[i] = input() l = len(a[i]) curr = 0 while l > 0 and curr < k: l -= 1 if a[i][l] in ve: curr += 1 if curr == k: a[i] = a[i][l:] else: a[i] = str(i) if a[0] == a[3] and a[1] == a[2]: abba = abba and 1 else: abba = 0 if a[0] == a[1] and a[2] == a[3]: aabb = aabb and 1 else: aabb = 0 if a[0] == a[2] and a[1] == a[3]: abab = abab and 1 else: abab = 0 if abba and aabb and abab: print('aaaa') elif not(abba or aabb or abab): print('NO') elif abba: print('abba') elif abab: print('abab') elif aabb: print('aabb') # Made By Mostafa_Khaled ```
output
1
5,223
6
10,447
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
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Tags: implementation Correct Solution: ``` n, k = map(int, input().split()) vowels = ['a', 'e', 'i', 'o', 'u'] def find_nth(tab, S, n): amount, pos = (1 if tab[0] in S else 0), 0 while pos < len(tab) and amount < n: pos += 1 if tab[pos] in S: amount += 1 return pos def rhyme_type(lines, k): suffixes = [] for line in lines: amount = 0 for i in line: if i in vowels: amount += 1 if amount < k: return 'TRASH' rev = list(reversed(list(line))) ind_from_front = find_nth(rev, vowels, k) suffixes.append(line[-ind_from_front - 1:]) if all([suffixes[0] == x for x in suffixes]): return 'aaaa' if suffixes[0] == suffixes[1] and suffixes[2] == suffixes[3]: return 'aabb' if suffixes[0] == suffixes[2] and suffixes[1] == suffixes[3]: return 'abab' if suffixes[0] == suffixes[3] and suffixes[1] == suffixes[2]: return 'abba' return 'TRASH' all_rhymes = set() for _ in range(n): lines = [input(), input(), input(), input()] all_rhymes.add(rhyme_type(lines, k)) if 'TRASH' not in all_rhymes and len(all_rhymes) == 2 and 'aaaa' in all_rhymes: all_rhymes.remove('aaaa') print(list(all_rhymes)[0]) elif len(all_rhymes) > 1 or 'TRASH' in all_rhymes: print('NO') else: print(list(all_rhymes)[0]) ```
output
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10,449
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
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Tags: implementation Correct Solution: ``` n, k = map(int, input().split()) def get_suffix(line): position = 0 for _ in range(k): position -= 1 while -position <= len(line) and line[position] not in 'aeiou': position -= 1 if -position > len(line): return '' return line[position:] common_rhyme_type = 'aaaa' for _ in range(n): s1, s2, s3, s4 = [get_suffix(input()) for _ in range(4)] if '' in (s1, s2, s3, s4): print('NO') break if s1 == s2 == s3 == s4: rhyme_type = 'aaaa' elif s1 == s2 and s3 == s4: rhyme_type = 'aabb' elif s1 == s3 and s2 == s4: rhyme_type = 'abab' elif s1 == s4 and s2 == s3: rhyme_type = 'abba' else: print('NO') break if rhyme_type != 'aaaa': if common_rhyme_type != 'aaaa' and rhyme_type != common_rhyme_type: print('NO') break else: common_rhyme_type = rhyme_type else: print(common_rhyme_type) ```
output
1
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10,451
Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
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Tags: implementation Correct Solution: ``` #------------------------template--------------------------# import os import sys from math import * from collections import * from fractions import * from bisect import * from heapq import* from io import BytesIO, IOBase def vsInput(): sys.stdin = open('input.txt', 'r') sys.stdout = open('output.txt', 'w') BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") ALPHA='abcdefghijklmnopqrstuvwxyz' M=10**9+7 EPS=1e-6 def value():return tuple(map(int,input().split())) def array():return [int(i) for i in input().split()] def Int():return int(input()) def Str():return input() def arrayS():return [i for i in input().split()] #-------------------------code---------------------------# # vsInput() ACCEPTED={'aaaa','aabb','abba','abab'} vowels='aeiou' nul='abcd' nu=0 def operate(s): global nu c=0 for i in range(len(s)-1,-1,-1): if(s[i] in vowels): c+=1 if(c==k): return s[i:] nu=(nu+1)%4 return nul[nu] def rhymes(a): a=[operate(i) for i in a] # print(a) ID={} id=0 ans='' for i in a: if(i not in ID): ID[i]=nul[id] id+=1 ans+=ID[i] return ans n,k=value() scheme=set() for i in range(n): a=[] for j in range(4): a.append(input()) scheme.add(rhymes(a)) # print(scheme) for i in scheme: if(i not in ACCEPTED): print("NO") exit() if(len(scheme)>2): print("NO") elif(len(scheme)==2): if('aaaa' not in scheme): print("NO") else: for i in scheme: if(i!='aaaa'): print(i) else: print(*scheme) ```
output
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Provide tags and a correct Python 3 solution for this coding contest problem. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO".
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Tags: implementation Correct Solution: ``` from sys import stdin read = stdin.readline n,k = map(int,read().split()) r = 0 vowel = {'a','e','i','o','u'} def cmp(a,b,k,vowel): l = 0 for x,y in zip(reversed(a),reversed(b)): if x != y: return False l += (x in vowel) if l == k: return True return False im = True for s in range(n): a,b,c,d = read(),read(),read(),read() l = 0 for i,x in enumerate(reversed(a),start=1): l += (x in vowel) if l == k: break else: print('NO') break b2,b3,b4 = (a[-i:] == b[-i:]),(a[-i:] == c[-i:]),(a[-i:] == d[-i:]) if b2 + b3 + b4 == 3: continue elif b2 + b3 + b4 == 1: if b2 and (r == 1 or r == 0) and cmp(c,d,k,vowel): r = 1 continue elif b3 and (r==2 or r == 0) and cmp(b,d,k,vowel): r = 2 continue elif b4 and (r == 3 or r == 0) and cmp(b,c,k,vowel): r = 3 continue print('NO') break else: print(['aaaa','aabb','abab','abba'][r]) ```
output
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10,455
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO". Submitted Solution: ``` n, k = map(int, input().split()) def get_suffix(line): position = -1 for _ in range(k): while -position <= len(line) and line[position] not in 'aeiou': position -= 1 if -position > len(line): return '' return line[position:] def detect_rhyme_type(quatrain): s1, s2, s3, s4 = [get_suffix(line) for line in quatrain] if s1 == s2 == s3 == s4: return 'aaaa' elif s1 == s2 and s3 == s4: return 'aabb' elif s1 == s3 and s2 == s4: return 'abab' elif s1 == s4 and s2 == s3: return 'abba' else: return 'NO' common_rhyme_type = 'aaaa' for _ in range(n): quatrain = [input() for _ in range(4)] rhyme_type = detect_rhyme_type(quatrain) if rhyme_type == 'NO': print('NO') break if rhyme_type != common_rhyme_type and common_rhyme_type != 'aaaa': print('NO') break else: common_rhyme_type = rhyme_type else: print(common_rhyme_type) ```
instruction
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No
output
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO". Submitted Solution: ``` n,k = map(int,input().split()) lis=[] vov=['a','e','i','o','u'] d={} d['aabb']=d['abab']=d['abba']=d['aaaa']=0 for i in range(n*4): s = input() lis.append(s) if i%4==3: tmp=['']*4 for j in range(4): s=lis[j] c=0 cou=0 for ll in s[::-1]: cou+=1 if ll in vov: c+=1 if c==k: tmp[j]=s[-cou:] break # print(tmp) if tmp[0]==tmp[1]==tmp[2]==tmp[3] and tmp[0]!='': d['aaaa']+=1 if tmp[0]==tmp[1] and tmp[2]==tmp[3] and tmp[1]!=tmp[3] and tmp[1]!='' and tmp[3]!='': d['aabb']+=1 elif tmp[0]==tmp[2] and tmp[1]==tmp[3] and tmp[1]!=tmp[0] and tmp[1]!='' and tmp[0]!='': d['abab']+=1 elif tmp[0]==tmp[3] and tmp[1]==tmp[2] and tmp[2]!=tmp[0] and tmp[1]!='' and tmp[3]!='': d['abba']+=1 else: print("NO") exit() lis=[] c=0 for i in d: if d[i]>0: c+=1 if c==1: for i in d: if d[i]>0: print(i) exit() elif c==2 and d['aaaa']>0: for i in d: if d[i]>0: print(i) exit() else: print("NO") ```
instruction
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No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO". Submitted Solution: ``` n, p = map(int, input().split()) final = [] fe = 0 for i in range(0, 4*n, 4): l = [] for j in range(4): s = input() temp = p error = 0 for k in range(len(s)-1, -1, -1): if(s[k] == 'a' or s[k] == 'e' or s[k] == 'i' or s[k] == 'o' or s[k] == 'u'): temp -= 1 if(temp == 0): l.append(s[k:]) break if(len(l) == 4): if(l[0] == l[1] and l[2] == l[3] and l[1] == l[2]): final.append(1) elif(l[0] == l[1] and l[2] == l[3]): final.append(2) elif(l[0] == l[2] and l[1] == l[3]): final.append(3) elif(l[0] == l[3] and l[2] == l[1]): final.append(4) else: fe = 1 if(len(l) == n): final = list(set(final)) # print(final) if(len(final) == 1): if(final[0] == 1): print("aaaa") elif(final[0] == 2): print("aabb") elif(final[0] == 3): print("abab") elif (final[0] == 4): print("abba") elif(len(final) == 2): if(final[0] == 1 or final[1] == 1): if(final[0] == 2): print("aabb") elif(final[0] == 3): print("abab") elif(final[0] == 4): print("abba") elif(final[1] == 2): print("aabb") elif(final[1] == 3): print("abab") elif(final[1] == 4): print("abba") else: print("NO") else: print("NO") else: print("NO") ```
instruction
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No
output
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6
10,461
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Vera adores poems. All the poems Vera knows are divided into quatrains (groups of four lines) and in each quatrain some lines contain rhymes. Let's consider that all lines in the poems consist of lowercase Latin letters (without spaces). Letters "a", "e", "i", "o", "u" are considered vowels. Two lines rhyme if their suffixes that start from the k-th vowels (counting from the end) match. If a line has less than k vowels, then such line can't rhyme with any other line. For example, if k = 1, lines commit and hermit rhyme (the corresponding suffixes equal it), and if k = 2, they do not rhyme (ommit ≠ ermit). Today on a literature lesson Vera learned that quatrains can contain four different schemes of rhymes, namely the following ones (the same letters stand for rhyming lines): * Clerihew (aabb); * Alternating (abab); * Enclosed (abba). If all lines of a quatrain pairwise rhyme, then the quatrain can belong to any rhyme scheme (this situation is represented by aaaa). If all quatrains of a poem belong to the same rhyme scheme, then we can assume that the whole poem belongs to this rhyme scheme. If in each quatrain all lines pairwise rhyme, then the rhyme scheme of the poem is aaaa. Let us note that it doesn't matter whether lines from different quatrains rhyme with each other or not. In other words, it is possible that different quatrains aren't connected by a rhyme. Vera got a long poem as a home task. The girl has to analyse it and find the poem rhyme scheme. Help Vera cope with the task. Input The first line contains two integers n and k (1 ≤ n ≤ 2500, 1 ≤ k ≤ 5) — the number of quatrains in the poem and the vowel's number, correspondingly. Next 4n lines contain the poem. Each line is not empty and only consists of small Latin letters. The total length of the lines does not exceed 104. If we assume that the lines are numbered starting from 1, then the first quatrain contains lines number 1, 2, 3, 4; the second one contains lines number 5, 6, 7, 8; and so on. Output Print the rhyme scheme of the poem as "aabb", "abab", "abba", "aaaa"; or "NO" if the poem does not belong to any of the above mentioned schemes. Examples Input 1 1 day may sun fun Output aabb Input 1 1 day may gray way Output aaaa Input 2 1 a a a a a a e e Output aabb Input 2 1 day may sun fun test hill fest thrill Output NO Note In the last sample both quatrains have rhymes but finding the common scheme is impossible, so the answer is "NO". Submitted Solution: ``` n, k = map(int, input().split()) vowels = ['a', 'e', 'i', 'o', 'u'] def find_nth(tab, S, n): amount, pos = (1 if tab[0] in S else 0), 0 while pos < len(tab) and amount < n: pos += 1 if tab[pos] in S: amount += 1 return pos def rhyme_type(lines, k): suffixes = [] for line in lines: amount = 0 for i in line: if i in vowels: amount += 1 if amount < k: return 'TRASH' rev = list(reversed(list(line))) ind_from_front = find_nth(rev, vowels, k) suffixes.append(line[-ind_from_front - 1:]) print(suffixes) if all([suffixes[0] == x for x in suffixes]): return 'aaaa' if suffixes[0] == suffixes[1] and suffixes[2] == suffixes[3]: return 'aabb' if suffixes[0] == suffixes[2] and suffixes[1] == suffixes[3]: return 'abab' if suffixes[0] == suffixes[3] and suffixes[1] == suffixes[2]: return 'abba' return 'TRASH' all_rhymes = set() for _ in range(n): lines = [input(), input(), input(), input()] all_rhymes.add(rhyme_type(lines, k)) if 'TRASH' not in all_rhymes and len(all_rhymes) == 2 and 'aaaa' in all_rhymes: all_rhymes.remove('aaaa') print(list(all_rhymes)[0]) elif len(all_rhymes) > 1 or 'TRASH' in all_rhymes: print('NO') else: print(list(all_rhymes)[0]) ```
instruction
0
5,231
6
10,462
No
output
1
5,231
6
10,463
Provide tags and a correct Python 3 solution for this coding contest problem. Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy. Input The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000). Output On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1. Examples Input banana 4 Output 2 baan Input banana 3 Output 3 nab Input banana 2 Output -1 Note In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".
instruction
0
5,339
6
10,678
Tags: binary search, constructive algorithms, greedy Correct Solution: ``` s = input() n = int(input()) d = {} r = 0 for a in s: d.setdefault(a, 0) d[a] += 1 if(d[a] > r): r = d[a] if (len(d) > n): print(-1) else: l = 0 while r - l > 1: k = (l + r) // 2 cur = 0 for x in d.values(): cur += (x+k-1) // k if cur > n: l = k else: r = k print(r) s = '' for a in d.keys(): s += a * ((d[a] + r - 1) // r) l=len(s) s += 'a' * (n-len(s)) print(s) ```
output
1
5,339
6
10,679
Provide tags and a correct Python 3 solution for this coding contest problem. Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy. Input The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000). Output On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1. Examples Input banana 4 Output 2 baan Input banana 3 Output 3 nab Input banana 2 Output -1 Note In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".
instruction
0
5,341
6
10,682
Tags: binary search, constructive algorithms, greedy Correct Solution: ``` import sys import os from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") import math s = input() n = int(input()) d = {} reserve = '' unique = 0 max_occur = 1 all_letters = '' for x in s: if x in d: d[x] += 1 if d[x] > max_occur: max_occur = d[x] else: d[x] = 1 unique += 1 all_letters += x if unique > n: print(-1) elif unique == n: print(max_occur) print(all_letters) else: l = 1 r = max_occur ans = max_occur check = 0 final_str = all_letters check_str = '' while l<=r: mid = l + (r-l)//2 check = 0 check_str = '' reserve = '' for i in d.keys(): if d[i] > mid: check += math.ceil(d[i]/mid) check_str += i*math.ceil(d[i]/mid) reserve += i*(d[i] - math.ceil(d[i]/mid)) else: check += 1 check_str += i reserve += i*(d[i]-1) if check <= n: final_str = '%s' % check_str if len(final_str) < n: final_str += reserve[:n-len(final_str)] if len(final_str) < n: final_str += 'a'*(n-len(final_str)) ans = mid r = mid-1 else: l = mid+1 print(ans) print(final_str) ```
output
1
5,341
6
10,683
Provide tags and a correct Python 3 solution for this coding contest problem. Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy. Input The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000). Output On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1. Examples Input banana 4 Output 2 baan Input banana 3 Output 3 nab Input banana 2 Output -1 Note In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".
instruction
0
5,342
6
10,684
Tags: binary search, constructive algorithms, greedy Correct Solution: ``` import math from sys import stdin from math import ceil if __name__ == '__main__': s = input() n = int(input()) dictionary = {} for i in s: if i in dictionary: dictionary[i] = dictionary[i] + 1 else: dictionary[i] = 1 if len(dictionary) > n: print(-1) else: if len(s) < n: print(1) newS = s else: lengthS = len(s) // n newLength = len(s) while lengthS < newLength: mid = (lengthS + newLength) // 2 total = 0 for i in dictionary: total = total + ceil(dictionary[i] / mid) if total > n: lengthS = mid + 1 else: newLength = mid print(lengthS) newS = '' for i in dictionary: for j in range(ceil(dictionary[i] / lengthS)): newS = newS + i for i in range(n - len(newS)): newS = newS + s[0] print(newS) ```
output
1
5,342
6
10,685
Provide tags and a correct Python 3 solution for this coding contest problem. Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy. Input The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000). Output On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1. Examples Input banana 4 Output 2 baan Input banana 3 Output 3 nab Input banana 2 Output -1 Note In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".
instruction
0
5,343
6
10,686
Tags: binary search, constructive algorithms, greedy Correct Solution: ``` from math import ceil s = input () n = int (input ()) count = {} for i in s: if i in count: count[i] += 1 else: count[i] = 1 if len(count) > n: print (-1) else: if len(s) < n: print (1) ret = s else: l,h = len (s)//n, len (s) while (l < h): m = (l+h) // 2 tot = 0 for i in count: tot += ceil (count[i]/m) if tot > n: l = m+1 else: h = m print (l) ret = '' for i in count: for j in range (ceil (count[i]/l)): ret += i for i in range (n-len(ret)): ret += s[0] print (ret) ```
output
1
5,343
6
10,687
Provide tags and a correct Python 3 solution for this coding contest problem. Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy. Input The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000). Output On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1. Examples Input banana 4 Output 2 baan Input banana 3 Output 3 nab Input banana 2 Output -1 Note In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".
instruction
0
5,344
6
10,688
Tags: binary search, constructive algorithms, greedy Correct Solution: ``` s = input() n = int(input()) symb_cnt = {} for c in s: symb_cnt[c] = symb_cnt[c] + 1 if c in symb_cnt else 1 for cnt in range(1, len(s) + 1): s1 = "" for c in symb_cnt: s1 += c * ((symb_cnt[c] + cnt - 1) // cnt) if len(s1) <= n: for i in range(n - len(s1)): s1 += 'a' print(cnt) print(s1) exit(0) print(-1) ```
output
1
5,344
6
10,689
Provide tags and a correct Python 3 solution for this coding contest problem. Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy. Input The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000). Output On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1. Examples Input banana 4 Output 2 baan Input banana 3 Output 3 nab Input banana 2 Output -1 Note In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".
instruction
0
5,345
6
10,690
Tags: binary search, constructive algorithms, greedy Correct Solution: ``` from collections import Counter def main(): s = input() l = int(input()) d = Counter(s) if len(d) > l: print(-1) return lo = 0 hi = 10000 while lo + 1 < hi: mid = (lo + hi) // 2 c = 0 for x in iter(d.values()): c += (x + mid - 1) // mid if c > l: lo = mid else: hi = mid print(hi) ans = [] for x in iter(d.items()): ans.append(x[0] * int(((x[1] + hi - 1) / hi))) t = ''.join(ans) if len(t) < l: t += 'a' * (l - len(t)) print(t) main() ```
output
1
5,345
6
10,691
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,462
6
10,924
Tags: dp, implementation, strings Correct Solution: ``` s = input() possible = [[],[],[False]*10100, [False]*10100] length = len(s) possible[2][length-2] = True possible[3][length-3] = True for i in range(length-1, 5-1,-1): if length - 4 >= i: possible[2][i] = (possible[2][i+2] and s[i:i+2] != s[i+2:i+4]) or possible[3][i+2] if length - 5 >= i: possible[3][i] = possible[2][i+3] if length - 6 >= i: possible[3][i] = (possible[3][i + 3] and s[i:i+3] != s[i+3:i+6]) or possible[3][i] output = set() for i in range(5,10000): if possible[2][i]: output.add(s[i:i + 2]) if possible[3][i]: output.add(s[i:i + 3]) output_list = sorted(list(output)) print(len(output_list)) for o in output_list: print(o) ```
output
1
5,462
6
10,925
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,463
6
10,926
Tags: dp, implementation, strings Correct Solution: ``` import sys value = input() if (len(value) < 7): print(0) sys.exit(0) res = set() possible = {} possible[len(value)] = set([2]) if (len(value) > 7): possible[len(value)].add(3) possibleLen = [2, 3] for i in reversed(range(7, len(value) + 1)): possibleVal = possible.get(i, set()) for length in possibleVal: nextI = i - length val = value[nextI:i] res.add(val) for posLen in possibleLen: if (nextI >= 5 + posLen and value[nextI - posLen:nextI] != val): setNextI = possible.setdefault(nextI, set()) setNextI.add(posLen) print(len(res)) for val in sorted(res): print(val) ```
output
1
5,463
6
10,927
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,464
6
10,928
Tags: dp, implementation, strings Correct Solution: ``` from sys import * setrecursionlimit(20000) dp = [] ans = [] def fun(s, pos, r, ln): if pos <= 4+ln: return 0 if dp[pos][ln-2] != 0: return dp[pos][ln-2] if s[pos-ln:pos] != r: dp[pos][ln-2] = 1 + fun(s, pos - ln, s[pos-ln:pos],2) + fun(s, pos - ln, s[pos-ln:pos],3) ans.append(s[pos-ln:pos]) ''' if pos > 4+ln and s[pos-3:pos] != r: dp[pos][1] = 1 + fun(s, pos - 3, s[pos-3:pos]) ans.append(s[pos-3:pos])''' return dp[pos][ln-2] s = input() dp = [[0, 0] for i in range(len(s) + 1)] fun(s, len(s), '', 2) fun(s, len(s), '', 3) ans = list(set(ans)) ans.sort() print (len(ans)) for i in ans: print (i) ```
output
1
5,464
6
10,929
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,465
6
10,930
Tags: dp, implementation, strings Correct Solution: ``` s = input() n = len(s) s += '0000000000' dp = [[0] * 2 for i in range(n + 5)] dp[n] = [1, 1] res = set() for i in range(n - 1, 4, -1): if i + 2 <= n and ((dp[i + 2][0] and s[i: i + 2] != s[i + 2: i + 4]) or dp[i + 2][1]): res.add(s[i: i + 2]) dp[i][0] = 1 if i + 3 <= n and ((dp[i + 3][1] and s[i: i + 3] != s[i + 3: i + 6]) or dp[i + 3][0]): res.add(s[i: i + 3]) dp[i][1] = 1 print(len(res)) for ss in sorted(res): print(ss) ```
output
1
5,465
6
10,931
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,466
6
10,932
Tags: dp, implementation, strings Correct Solution: ``` __author__ = 'Utena' s=input() n=len(s) ans=set() if n<=6: print(0) exit(0) dp=[[False,False]for i in range(n+1)] if n>7: dp[3][1]=True ans.add(s[-3:]) dp[2][0]=True ans.add(s[-2:]) for i in range(4,n-4): if s[(-i):(-i+2)]!=s[(-i+2):(-i+3)]+s[-i+3]and dp[i-2][0] or dp[i-2][1]: dp[i][0]=True ans|={s[(-i):(-i+2)]} if i>=6 and s[(-i):(-i+3)]!=s[(-i+3):(-i+5)]+s[-i+5]and dp[i-3][1] or dp[i-3][0]: dp[i][1]=True ans.add(s[(-i):(-i+3)]) ans=sorted(list(ans)) print(len(ans)) print('\n'.join(ans)) ```
output
1
5,466
6
10,933
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,467
6
10,934
Tags: dp, implementation, strings Correct Solution: ``` def main(): s = input()[5:] n = len(s) if n < 2: print(0) return res2, res3 = set(), set() dp2 = [False] * (n + 1) dp3 = [False] * (n + 1) dp2[-1] = dp3[-1] = True for i in range(n, 1, -1): if dp3[i] or dp2[i] and s[i - 2:i] != s[i:i + 2]: res2.add(s[i - 2:i]) dp2[i - 2] = True if dp2[i] or dp3[i] and s[i - 3:i] != s[i:i + 3]: res3.add(s[i - 3:i]) dp3[i - 3] = True res3.discard(s[i - 3:i]) res3.update(res2) print(len(res3)) for s in sorted(res3): print(s) if __name__ == '__main__': main() ```
output
1
5,467
6
10,935
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,468
6
10,936
Tags: dp, implementation, strings Correct Solution: ``` def getPossibleSuffixes(s): if len(s) == 5: print(0) return possible_suffixes = s[5:len(s)] suffixes = [] helper_hash = {} suffix_starts = [0 for x in range(len(possible_suffixes))] prev_2 = ["" for x in range(len(possible_suffixes))] suffix_starts[-1] = 1 for i in range(len(possible_suffixes)-2, -1, -1): if suffix_starts[i+1] and prev_2[i+1] != possible_suffixes[i:i+2]: if not helper_hash.get(possible_suffixes[i:i+2]): suffixes.append(possible_suffixes[i:i+2]) helper_hash[possible_suffixes[i:i+2]] = True if i-1>=0: prev_2[i-1] = possible_suffixes[i:i+2] suffix_starts[i-1] = 1 if i+2 < len(possible_suffixes) and suffix_starts[i+2] and prev_2[i+2] != possible_suffixes[i:i+3]: if not helper_hash.get(possible_suffixes[i:i+3]): suffixes.append(possible_suffixes[i:i+3]) helper_hash[possible_suffixes[i:i+3]] = True if i-1>=0: if prev_2[i-1] != "": prev_2[i-1] = "" else: prev_2[i-1] = possible_suffixes[i:i+3] suffix_starts[i-1] = 1 print(len(suffixes)) suffixes.sort() for suffix in suffixes: print(suffix) s = input() getPossibleSuffixes(s) ```
output
1
5,468
6
10,937
Provide tags and a correct Python 3 solution for this coding contest problem. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
instruction
0
5,469
6
10,938
Tags: dp, implementation, strings Correct Solution: ``` string = input() s = set() finded = {} import sys sys.setrecursionlimit(900000000) def get_substr(string, start, parent): # базовый случай if start >= len(string): return if start+1 < len(string): substr = string[start:start+2] # проверим не та же ли это строка if substr != parent: s.add(substr) if (start+2, 2) not in finded: get_substr(string, start+2, substr) finded[(start+2, 2)] = True if start+2 < len(string): substr = string[start:start+3] # проверим не та же ли это строка if substr != parent: s.add(substr) if (start+3, 3) not in finded: get_substr(string, start+3, substr) finded[(start+3, 3)] = True get_substr(string[5:][::-1], 0, "") print(len(s)) ans = [] for i in s: ans.append(i[::-1]) for a in sorted(ans): print(a) ```
output
1
5,469
6
10,939
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` from sys import * setrecursionlimit(200000) d = {} t = set() s = input() + ' ' def gen(l, ll): if (l, ll) in t: return t.add((l, ll)) if l > 6: d[s[l - 2 : l]] = 1 if s[l - 2 : l] != s[l : ll]: gen(l - 2, l) if l > 7: d[s[l - 3 : l]] = 1 if s[l - 3 : l] != s[l : ll]: gen(l - 3, l) gen(len(s) - 1,len(s)) print(len(d)) for k in sorted(d): print(k) ```
instruction
0
5,470
6
10,940
Yes
output
1
5,470
6
10,941
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` import sys input = sys.stdin.readline s = input().strip() n = len(s) poss = [[False] * 2 for _ in range(n)] poss[n - 2][0] = poss[n - 3][1] = True for i in range(n - 4, -1, -1): poss[i][0] = s[i: i + 2] != s[i + 2: i + 4] and poss[i + 2][0] or poss[i + 2][1] poss[i][1] = s[i: i + 3] != s[i + 3: i + 6] and poss[i + 3][1] or poss[i + 3][0] ans = set() for i in range(5, n): if poss[i][0]: ans.add(s[i: i + 2]) if poss[i][1]: ans.add(s[i:i + 3]) print(len(ans)) for x in sorted(ans): print(x) ```
instruction
0
5,471
6
10,942
Yes
output
1
5,471
6
10,943
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` t = input() s, d = set(), set() p = {(len(t), 2)} while p: m, x = p.pop() r = m + x for y in [x, 5 - x]: l = m - y q = (l, y) if q in d or l < 5 or t[l:m] == t[m:r]: continue s.add(t[l:m]) d.add(q) p.add(q) print(len(s)) print('\n'.join(sorted(s))) # Made By Mostafa_Khaled ```
instruction
0
5,472
6
10,944
Yes
output
1
5,472
6
10,945
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` s = input() n = len(s) dp2,dp3=[0 for i in range(n)],[0 for i in range(n)] if(n<7): print(0) else: if n-2>4: dp2[n-2]=1 if n-3>4: dp3[n-3]=1; i=n-4 while i>=5: dp2[i]=(dp3[i+2] | (dp2[i+2] & (s[i:i+2]!=s[i+2:i+4]) ) ) dp3[i]=dp2[i+3] | (dp3[i+3] & (s[i:i+3]!=s[i+3:i+6]) ) i=i-1 a=set() for i in range(n): if dp2[i]:a.add(s[i:i+2]) if dp3[i]:a.add(s[i:i+3]) a=sorted(list(a)) print(len(a)) for i in a: print(i) ```
instruction
0
5,473
6
10,946
Yes
output
1
5,473
6
10,947
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` s = input() if len(s) <= 5: print(0) else: words = set() s = s[5:] r = len(s) for j in range(r, 1, -1): if j == r - 1: continue if j == 2: words.add(s[0:2]) continue words.add(s[j - 2:j]) words.add(s[j - 3:j]) print(len(words)) for word in sorted(words): print(word) ```
instruction
0
5,474
6
10,948
No
output
1
5,474
6
10,949
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` for _ in range(1): st=input() n=len(st) if n<=6: print(0) continue i=5 d=set() for i in range(5,n-1): if i==n-4: d.add(str(st[i])+str(st[i+1])) elif i==n-3: d.add(str(st[i])+str(st[i+1])+str(st[i+2])) else: if i<=n-2: d.add(str(st[i])+str(st[i+1])) if i<=n-3: d.add(str(st[i]) + str(st[i + 1]) + str(st[i + 2])) arr=[] for i in d: arr.append(i) arr.sort() print(len(arr)) for i in arr: print(i) ```
instruction
0
5,475
6
10,950
No
output
1
5,475
6
10,951
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` def getPossibleSuffixes(s): if len(s) == 5: print(0) return possible_suffixes = s[5:len(s)] suffixes = [] suffix_starts = [0 for x in range(len(possible_suffixes))] prev_2 = ["" for x in range(len(possible_suffixes))] prev_3 = ["" for x in range(len(possible_suffixes))] suffix_starts[-1] = 1 for i in range(len(possible_suffixes)-2, -1, -1): if suffix_starts[i+1] and prev_2[i+1] != possible_suffixes[i:i+2]: if possible_suffixes[i:i+2] not in suffixes: suffixes.append(possible_suffixes[i:i+2]) if i-1>=0: prev_2[i-1] = possible_suffixes[i:i+2] suffix_starts[i-1] = 1 if i+2 < len(possible_suffixes) and suffix_starts[i+2] and prev_3[i+2] != possible_suffixes[i:i+3]: if possible_suffixes[i:i+3] not in suffixes: suffixes.append(possible_suffixes[i:i+3]) if i-1>=0: prev_3[i-1] = possible_suffixes[i:i+3] suffix_starts[i-1] = 1 print(len(suffixes)) suffixes.sort() for suffix in suffixes: print(suffix) s = input() getPossibleSuffixes(s) ```
instruction
0
5,476
6
10,952
No
output
1
5,476
6
10,953
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction — it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. Input The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters. Output On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. Print suffixes in lexicographical (alphabetical) order. Examples Input abacabaca Output 3 aca ba ca Input abaca Output 0 Note The first test was analysed in the problem statement. In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix. Submitted Solution: ``` __author__ = 'Utena' s=input() n=len(s) ans=set() if n<=6: print(0) exit(0) dp=[[False,False]for i in range(n+1)] if n>6:dp[3][1]=True dp[2][0]=True ans.add(s[-2:]) ans.add(s[-3:]) for i in range(4,n-4): if s[(-i):(-i+2)]!=s[(-i+2):(-i+4)]and dp[i-2][0] or dp[i-2][1]: dp[i][0]=True ans|={s[(-i):(-i+2)]} if i>=6 and s[(-i):(-i+3)]!=s[(-i+3):(-i+6)]and dp[i-3][1] or dp[i-3][0]: dp[i][1]=True ans.add(s[(-i):(-i+3)]) ans=sorted(list(ans)) print(len(ans)) print('\n'.join(ans)) ```
instruction
0
5,477
6
10,954
No
output
1
5,477
6
10,955
Provide tags and a correct Python 3 solution for this coding contest problem. Thanks to your help, Heidi is confident that no one can fool her. She has now decided to post some fake news on the HC2 Facebook page. However, she wants to be able to communicate to the HC2 committee that the post is fake, using some secret phrase hidden in the post as a subsequence. To make this method foolproof, she wants the phrase to appear n times in the post. She is asking you to design a post (string) s and a hidden phrase p such that p appears in s as a subsequence exactly n times. Input The first and only line of input contains a single integer n (1 ≤ n ≤ 1 000 000). Output The output should contain two nonempty strings s and p separated by a single space. Each string should be composed of letters (a-z and A-Z: both lowercase and uppercase are allowed) and have length at most 200. The number of occurrences of p in s as a subsequence should be exactly n. If there are many possible solutions, output any of them. It is guaranteed that at least one solution exists. Examples Input 2 Output hHheidi Hei Input 4 Output bbbba ba Input 6 Output aaabb ab Note An occurrence of p as a subsequence in s should be thought of as a set of positions in s such that the letters at these positions, in order, form p. The number of occurences is thus the number of such sets. For example, ab appears 6 times as a subsequence in aaabb, for the following sets of positions: {1, 4}, {1, 5}, {2, 4}, {2, 5}, {3, 4}, {3, 5} (that is, we should choose one of the a's and one of the b's).
instruction
0
5,531
6
11,062
Tags: constructive algorithms, strings Correct Solution: ``` def rek(k): if k == 1: return ('a', 'a') elif k == 2: return ('aa', 'a') s, p = rek((k - 1) // 2) x = chr(ord(p[-1]) + 1) return (p + x * (2 - k % 2) + s[len(p):] + 2 * x, p + x) s, p = rek(int(input())) print(s, p) ```
output
1
5,531
6
11,063
Provide tags and a correct Python 3 solution for this coding contest problem. Thanks to your help, Heidi is confident that no one can fool her. She has now decided to post some fake news on the HC2 Facebook page. However, she wants to be able to communicate to the HC2 committee that the post is fake, using some secret phrase hidden in the post as a subsequence. To make this method foolproof, she wants the phrase to appear n times in the post. She is asking you to design a post (string) s and a hidden phrase p such that p appears in s as a subsequence exactly n times. Input The first and only line of input contains a single integer n (1 ≤ n ≤ 1 000 000). Output The output should contain two nonempty strings s and p separated by a single space. Each string should be composed of letters (a-z and A-Z: both lowercase and uppercase are allowed) and have length at most 200. The number of occurrences of p in s as a subsequence should be exactly n. If there are many possible solutions, output any of them. It is guaranteed that at least one solution exists. Examples Input 2 Output hHheidi Hei Input 4 Output bbbba ba Input 6 Output aaabb ab Note An occurrence of p as a subsequence in s should be thought of as a set of positions in s such that the letters at these positions, in order, form p. The number of occurences is thus the number of such sets. For example, ab appears 6 times as a subsequence in aaabb, for the following sets of positions: {1, 4}, {1, 5}, {2, 4}, {2, 5}, {3, 4}, {3, 5} (that is, we should choose one of the a's and one of the b's).
instruction
0
5,532
6
11,064
Tags: constructive algorithms, strings Correct Solution: ``` def getstr(n): if n==1: return 'a','',1 elif n==2: return 'ab','b',2 else: if n%2==0: p,u,now=getstr((n-2)//2) c = chr(ord('a')+now) return p+c,c+u+c+c,now+1 else: p,u,now=getstr((n-1)//2) c = chr(ord('a')+now) return p+c,u+c+c,now+1 n = int(input()) ans = getstr(n) print(ans[0]+ans[1],ans[0]) ```
output
1
5,532
6
11,065
Provide tags and a correct Python 3 solution for this coding contest problem. Thanks to your help, Heidi is confident that no one can fool her. She has now decided to post some fake news on the HC2 Facebook page. However, she wants to be able to communicate to the HC2 committee that the post is fake, using some secret phrase hidden in the post as a subsequence. To make this method foolproof, she wants the phrase to appear n times in the post. She is asking you to design a post (string) s and a hidden phrase p such that p appears in s as a subsequence exactly n times. Input The first and only line of input contains a single integer n (1 ≤ n ≤ 1 000 000). Output The output should contain two nonempty strings s and p separated by a single space. Each string should be composed of letters (a-z and A-Z: both lowercase and uppercase are allowed) and have length at most 200. The number of occurrences of p in s as a subsequence should be exactly n. If there are many possible solutions, output any of them. It is guaranteed that at least one solution exists. Examples Input 2 Output hHheidi Hei Input 4 Output bbbba ba Input 6 Output aaabb ab Note An occurrence of p as a subsequence in s should be thought of as a set of positions in s such that the letters at these positions, in order, form p. The number of occurences is thus the number of such sets. For example, ab appears 6 times as a subsequence in aaabb, for the following sets of positions: {1, 4}, {1, 5}, {2, 4}, {2, 5}, {3, 4}, {3, 5} (that is, we should choose one of the a's and one of the b's).
instruction
0
5,533
6
11,066
Tags: constructive algorithms, strings Correct Solution: ``` def solve(k): if k == 1: return ('a', 'a') if k == 2: return ('aa', 'a') s, p = solve((k-1) // 2) x = chr(ord(p[-1])+1) return (p+x*(2-k%2)+s[len(p):]+x*2, p+x) s, p = solve(int(input())) print(s, p) ```
output
1
5,533
6
11,067
Provide tags and a correct Python 3 solution for this coding contest problem. Thanks to your help, Heidi is confident that no one can fool her. She has now decided to post some fake news on the HC2 Facebook page. However, she wants to be able to communicate to the HC2 committee that the post is fake, using some secret phrase hidden in the post as a subsequence. To make this method foolproof, she wants the phrase to appear n times in the post. She is asking you to design a post (string) s and a hidden phrase p such that p appears in s as a subsequence exactly n times. Input The first and only line of input contains a single integer n (1 ≤ n ≤ 1 000 000). Output The output should contain two nonempty strings s and p separated by a single space. Each string should be composed of letters (a-z and A-Z: both lowercase and uppercase are allowed) and have length at most 200. The number of occurrences of p in s as a subsequence should be exactly n. If there are many possible solutions, output any of them. It is guaranteed that at least one solution exists. Examples Input 2 Output hHheidi Hei Input 4 Output bbbba ba Input 6 Output aaabb ab Note An occurrence of p as a subsequence in s should be thought of as a set of positions in s such that the letters at these positions, in order, form p. The number of occurences is thus the number of such sets. For example, ab appears 6 times as a subsequence in aaabb, for the following sets of positions: {1, 4}, {1, 5}, {2, 4}, {2, 5}, {3, 4}, {3, 5} (that is, we should choose one of the a's and one of the b's).
instruction
0
5,534
6
11,068
Tags: constructive algorithms, strings Correct Solution: ``` import string alphabet = list(string.ascii_lowercase + string.ascii_uppercase) def calc(n): if n == 1: return '', 'a' if n == 2: return 'a', 'a' if n % 2 == 1: u, p = calc(n//2) x = alphabet.pop() return u+x+x, p+x else: u, p = calc(n//2-1) x = alphabet.pop() return x+u+x+x, p+x n = int(input()) u, p = calc(n) print(p+u+' '+p) ```
output
1
5,534
6
11,069
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,237
6
12,474
Tags: sortings, strings Correct Solution: ``` n = int(input()) def comp(a, b): l = a + b r = b + a if l < r: return -1 elif l == r: return 0 else: return 1 from functools import cmp_to_key d = [] for _ in range(n): s = input().rstrip() d.append(s) d.sort(key=cmp_to_key(comp)) print(''.join(d)) ```
output
1
6,237
6
12,475
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,238
6
12,476
Tags: sortings, strings Correct Solution: ``` #### IMPORTANT LIBRARY #### ############################ ### DO NOT USE import random --> 250ms to load the library ############################ ### In case of extra libraries: https://github.com/cheran-senthil/PyRival ###################### ####### IMPORT ####### ###################### from functools import cmp_to_key from collections import deque, Counter from heapq import heappush, heappop from math import log, ceil ###################### #### STANDARD I/O #### ###################### import sys import os from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") if sys.version_info[0] < 3: sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout) else: sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) def print(*args, **kwargs): sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout) at_start = True for x in args: if not at_start: file.write(sep) file.write(str(x)) at_start = False file.write(kwargs.pop("end", "\n")) if kwargs.pop("flush", False): file.flush() def inp(): return sys.stdin.readline().rstrip("\r\n") # for fast input def ii(): return int(inp()) def si(): return str(inp()) def li(lag = 0): l = list(map(int, inp().split())) if lag != 0: for i in range(len(l)): l[i] += lag return l def mi(lag = 0): matrix = list() for i in range(n): matrix.append(li(lag)) return matrix def lsi(): #string list return list(map(str, inp().split())) def print_list(lista, space = " "): print(space.join(map(str, lista))) ###################### ### BISECT METHODS ### ###################### def bisect_left(a, x): """i tale che a[i] >= x e a[i-1] < x""" left = 0 right = len(a) while left < right: mid = (left+right)//2 if a[mid] < x: left = mid+1 else: right = mid return left def bisect_right(a, x): """i tale che a[i] > x e a[i-1] <= x""" left = 0 right = len(a) while left < right: mid = (left+right)//2 if a[mid] > x: right = mid else: left = mid+1 return left def bisect_elements(a, x): """elementi pari a x nell'árray sortato""" return bisect_right(a, x) - bisect_left(a, x) ###################### ### MOD OPERATION #### ###################### MOD = 10**9 + 7 maxN = 5 FACT = [0] * maxN INV_FACT = [0] * maxN def add(x, y): return (x+y) % MOD def multiply(x, y): return (x*y) % MOD def power(x, y): if y == 0: return 1 elif y % 2: return multiply(x, power(x, y-1)) else: a = power(x, y//2) return multiply(a, a) def inverse(x): return power(x, MOD-2) def divide(x, y): return multiply(x, inverse(y)) def allFactorials(): FACT[0] = 1 for i in range(1, maxN): FACT[i] = multiply(i, FACT[i-1]) def inverseFactorials(): n = len(INV_FACT) INV_FACT[n-1] = inverse(FACT[n-1]) for i in range(n-2, -1, -1): INV_FACT[i] = multiply(INV_FACT[i+1], i+1) def coeffBinom(n, k): if n < k: return 0 return multiply(FACT[n], multiply(INV_FACT[k], INV_FACT[n-k])) ###################### #### GRAPH ALGOS ##### ###################### # ZERO BASED GRAPH def create_graph(n, m, undirected = 1, unweighted = 1): graph = [[] for i in range(n)] if unweighted: for i in range(m): [x, y] = li(lag = -1) graph[x].append(y) if undirected: graph[y].append(x) else: for i in range(m): [x, y, w] = li(lag = -1) w += 1 graph[x].append([y,w]) if undirected: graph[y].append([x,w]) return graph def create_tree(n, unweighted = 1): children = [[] for i in range(n)] if unweighted: for i in range(n-1): [x, y] = li(lag = -1) children[x].append(y) children[y].append(x) else: for i in range(n-1): [x, y, w] = li(lag = -1) w += 1 children[x].append([y, w]) children[y].append([x, w]) return children def dist(tree, n, A, B = -1): s = [[A, 0]] massimo, massimo_nodo = 0, 0 distanza = -1 v = [-1] * n while s: el, dis = s.pop() if dis > massimo: massimo = dis massimo_nodo = el if el == B: distanza = dis for child in tree[el]: if v[child] == -1: v[child] = 1 s.append([child, dis+1]) return massimo, massimo_nodo, distanza def diameter(tree): _, foglia, _ = dist(tree, n, 0) diam, _, _ = dist(tree, n, foglia) return diam def dfs(graph, n, A): v = [-1] * n s = [[A, 0]] v[A] = 0 while s: el, dis = s.pop() for child in graph[el]: if v[child] == -1: v[child] = dis + 1 s.append([child, dis + 1]) return v #visited: -1 if not visited, otherwise v[B] is the distance in terms of edges def bfs(graph, n, A): v = [-1] * n s = deque() s.append([A, 0]) v[A] = 0 while s: el, dis = s.popleft() for child in graph[el]: if v[child] == -1: v[child] = dis + 1 s.append([child, dis + 1]) return v #visited: -1 if not visited, otherwise v[B] is the distance in terms of edges #FROM A GIVEN ROOT, RECOVER THE STRUCTURE def parents_children_root_unrooted_tree(tree, n, root = 0): q = deque() visited = [0] * n parent = [-1] * n children = [[] for i in range(n)] q.append(root) while q: all_done = 1 visited[q[0]] = 1 for child in tree[q[0]]: if not visited[child]: all_done = 0 q.appendleft(child) if all_done: for child in tree[q[0]]: if parent[child] == -1: parent[q[0]] = child children[child].append(q[0]) q.popleft() return parent, children # CALCULATING LONGEST PATH FOR ALL THE NODES def all_longest_path_passing_from_node(parent, children, n): q = deque() visited = [len(children[i]) for i in range(n)] downwards = [[0,0] for i in range(n)] upward = [1] * n longest_path = [1] * n for i in range(n): if not visited[i]: q.append(i) downwards[i] = [1,0] while q: node = q.popleft() if parent[node] != -1: visited[parent[node]] -= 1 if not visited[parent[node]]: q.append(parent[node]) else: root = node for child in children[node]: downwards[node] = sorted([downwards[node][0], downwards[node][1], downwards[child][0] + 1], reverse = True)[0:2] s = [node] while s: node = s.pop() if parent[node] != -1: if downwards[parent[node]][0] == downwards[node][0] + 1: upward[node] = 1 + max(upward[parent[node]], downwards[parent[node]][1]) else: upward[node] = 1 + max(upward[parent[node]], downwards[parent[node]][0]) longest_path[node] = downwards[node][0] + downwards[node][1] + upward[node] - min([downwards[node][0], downwards[node][1], upward[node]]) - 1 for child in children[node]: s.append(child) return longest_path ### TBD SUCCESSOR GRAPH 7.5 ### TBD TREE QUERIES 10.2 da 2 a 4 ### TBD ADVANCED TREE 10.3 ### TBD GRAPHS AND MATRICES 11.3.3 e 11.4.3 e 11.5.3 (ON GAMES) ###################### ## END OF LIBRARIES ## ###################### n = ii() lista = [] for i in range(n): lista.append(si()) def custom_sort(lista): def cmp(x,y): if x+y>y+x: return 1 else: return -1 return sorted(lista, key = cmp_to_key(cmp)) lista = custom_sort(lista) print_list(lista, "") ```
output
1
6,238
6
12,477
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,239
6
12,478
Tags: sortings, strings Correct Solution: ``` from functools import cmp_to_key def cmp(a,b): return -1 if a+b < b+a else 0 def main(): n = int(input()) l = [input() for i in range(n)] l = sorted(l,key=cmp_to_key(cmp)) for i in l: print(i,end="") if __name__ == "__main__": main() ```
output
1
6,239
6
12,479
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,241
6
12,482
Tags: sortings, strings Correct Solution: ``` from functools import cmp_to_key n = int(input()) l = [] for i in range(n): l.append(input()) l.sort(key = cmp_to_key(lambda x,y : 1 if x+y > y+x else -1)) print(''.join(l)) ```
output
1
6,241
6
12,483
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,242
6
12,484
Tags: sortings, strings Correct Solution: ``` # List = [[10,1],[20,2],[10,3]] --> Initial # List = [[10, 1], [10, 3], [20, 2]] --> Normal Sort # List = [[10, 3], [10, 1], [20, 2]] --> Sort with custom key [ascending, descending] from functools import cmp_to_key def custom(x,y): a = x +y b = y+ x if(a < b): return -1 elif(b < a): return 1 else: return 0 n = int(input()) arr = [] for i in range(n): s = input() arr.append(s) # arr.sort(key = cmp) arr.sort(key = cmp_to_key(custom)) # print(arr) ans = "" for i in arr: ans += i print(ans) ```
output
1
6,242
6
12,485
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,243
6
12,486
Tags: sortings, strings Correct Solution: ``` from bisect import insort,bisect_right,bisect_left from sys import stdout, stdin, setrecursionlimit from heapq import heappush, heappop, heapify from io import BytesIO, IOBase from collections import * from itertools import * from random import * from string import * from queue import * from math import * from re import * from os import * # sqrt,ceil,floor,factorial,gcd,log2,log10,comb ####################################---fast-input-output----######################################### class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = read(self._fd, max(fstat(self._fd).st_size, 8192)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = read(self._fd, max(fstat(self._fd).st_size, 8192)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") stdin, stdout = IOWrapper(stdin), IOWrapper(stdout) graph, mod, szzz = {}, 10**9 + 7, lambda: sorted(zzz()) def getStr(): return input() def getInt(): return int(input()) def listStr(): return list(input()) def getStrs(): return input().split() def isInt(s): return '0' <= s[0] <= '9' def input(): return stdin.readline().strip() def zzz(): return [int(i) for i in input().split()] def output(answer, end='\n'): stdout.write(str(answer) + end) def lcd(xnum1, xnum2): return (xnum1 * xnum2 // gcd(xnum1, xnum2)) def getPrimes(N = 10**5): SN = int(sqrt(N)) sieve = [i for i in range(N+1)] sieve[1] = 0 for i in sieve: if i > SN: break if i == 0: continue for j in range(2*i, N+1, i): sieve[j] = 0 prime = [i for i in range(N+1) if sieve[i] != 0] return prime def primeFactor(n,prime=getPrimes()): lst = [] mx=int(sqrt(n))+1 for i in prime: if i>mx:break while n%i==0: lst.append(i) n//=i if n>1: lst.append(n) return lst dx = [-1, 1, 0, 0, 1, -1, 1, -1] dy = [0, 0, 1, -1, 1, -1, -1, 1] daysInMounth = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] #################################################---Some Rule For Me To Follow---################################# """ --instants of Reading problem continuously try to understand them. --Try & again try, maybe you're just one statement away! """ ##################################################---START-CODING---############################################### num = getInt() lst=[] for _ in range(num): lst.append(getStr()) def mergeSort(s): if len(s)==1: return s s1 = mergeSort(s[:len(s)//2]) s2 = mergeSort(s[len(s)//2:]) return merge(s1,s2) def merge(s1,s2): lst=[] ind1 = 0 ind2 = 0 while ind1!=len(s1) and ind2 != len(s2): if s1[ind1]+s2[ind2]>s2[ind2]+s1[ind1]: lst.append(s2[ind2]) ind2+=1 else: lst.append(s1[ind1]) ind1+=1 if ind1 != len(s1): lst+=s1[ind1:] else: lst+=s2[ind2:] return lst print(''.join(i for i in mergeSort(lst))) ```
output
1
6,243
6
12,487
Provide tags and a correct Python 3 solution for this coding contest problem. You're given a list of n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest. Given the list of strings, output the lexicographically smallest concatenation. Input The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104). Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104. Output Print the only string a — the lexicographically smallest string concatenation. Examples Input 4 abba abacaba bcd er Output abacabaabbabcder Input 5 x xx xxa xxaa xxaaa Output xxaaaxxaaxxaxxx Input 3 c cb cba Output cbacbc
instruction
0
6,244
6
12,488
Tags: sortings, strings Correct Solution: ``` def cmp_to_key(mycmp): 'Convert a cmp= function into a key= function' class K: def __init__(self, obj, *args): self.obj = obj def __lt__(self, other): return mycmp(self.obj, other.obj) < 0 def __gt__(self, other): return mycmp(self.obj, other.obj) > 0 def __eq__(self, other): return mycmp(self.obj, other.obj) == 0 def __le__(self, other): return mycmp(self.obj, other.obj) <= 0 def __ge__(self, other): return mycmp(self.obj, other.obj) >= 0 def __ne__(self, other): return mycmp(self.obj, other.obj) != 0 return K n = int(input()) ls = [input() for _ in range(n)] def compare_str(x, y): if x + y < y + x: return -1 elif x + y > y + x: return 1 else: return 0 ls.sort(key=cmp_to_key(compare_str)) print("".join(ls)) ```
output
1
6,244
6
12,489