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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a string s of length n. Each character is either one of the first k lowercase Latin letters or a question mark. You are asked to replace every question mark with one of the first k lowercase Latin letters in such a way that the following value is maximized. Let f_i be the maximum length substring of string s, which consists entirely of the i-th Latin letter. A substring of a string is a contiguous subsequence of that string. If the i-th letter doesn't appear in a string, then f_i is equal to 0. The value of a string s is the minimum value among f_i for all i from 1 to k. What is the maximum value the string can have? Input The first line contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 17) — the length of the string and the number of first Latin letters used. The second line contains a string s, consisting of n characters. Each character is either one of the first k lowercase Latin letters or a question mark. Output Print a single integer — the maximum value of the string after every question mark is replaced with one of the first k lowercase Latin letters. Examples Input 10 2 a??ab????b Output 4 Input 9 4 ????????? Output 2 Input 2 3 ?? Output 0 Input 15 3 ??b?babbc??b?aa Output 3 Input 4 4 cabd Output 1 Note In the first example the question marks can be replaced in the following way: "aaaababbbb". f_1 = 4, f_2 = 4, thus the answer is 4. Replacing it like this is also possible: "aaaabbbbbb". That way f_1 = 4, f_2 = 6, however, the minimum of them is still 4. In the second example one of the possible strings is "aabbccdda". In the third example at least one letter won't appear in the string, thus, the minimum of values f_i is always 0. Submitted Solution: ``` from collections import deque import bisect n, k = map(int,input().split()) s = input() n=200000 k=15 s = "?"*200000 effectj = [[] for i in range(1<<k)] for state in range(1<<k): for j in range(k): if (1<<j) & state>0: effectj[state].append(j) maxconseq = [[0 for j in range(k)] for i in range(n+1)] for i in range(n): if s[i]=='?': for j in range(k): maxconseq[i][j] = maxconseq[i-1][j] + 1 else: j = ord(s[i])-97 maxconseq[i][j] = maxconseq[i-1][j] + 1 #print(maxconseq) def judge(needed): minstate = [2147483647]*(1<<k) minstate[0] = -1 effect = [[] for i in range(k)] for i in range(n): for j in range(k): if maxconseq[i][j]>=needed: effect[j].append(i) for state in range(1<<k): for j in effectj[state]: if effect[j] and minstate[state-(1<<j)] + needed > effect[j][-1]: continue loc = bisect.bisect_left(effect[j], minstate[state-(1<<j)] + needed) minstate[state] = min(minstate[state], effect[j][loc]) if minstate[-1]<n: return True return False front = 0 rear = n//k+1 while front < rear: mid = (front+rear)//2 flag = judge(mid) print(mid,flag) if flag: front = mid + 1 else: rear = mid print(front-1) ```
instruction
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91,182
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1
91,182
0
182,365
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a string s of length n. Each character is either one of the first k lowercase Latin letters or a question mark. You are asked to replace every question mark with one of the first k lowercase Latin letters in such a way that the following value is maximized. Let f_i be the maximum length substring of string s, which consists entirely of the i-th Latin letter. A substring of a string is a contiguous subsequence of that string. If the i-th letter doesn't appear in a string, then f_i is equal to 0. The value of a string s is the minimum value among f_i for all i from 1 to k. What is the maximum value the string can have? Input The first line contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 17) — the length of the string and the number of first Latin letters used. The second line contains a string s, consisting of n characters. Each character is either one of the first k lowercase Latin letters or a question mark. Output Print a single integer — the maximum value of the string after every question mark is replaced with one of the first k lowercase Latin letters. Examples Input 10 2 a??ab????b Output 4 Input 9 4 ????????? Output 2 Input 2 3 ?? Output 0 Input 15 3 ??b?babbc??b?aa Output 3 Input 4 4 cabd Output 1 Note In the first example the question marks can be replaced in the following way: "aaaababbbb". f_1 = 4, f_2 = 4, thus the answer is 4. Replacing it like this is also possible: "aaaabbbbbb". That way f_1 = 4, f_2 = 6, however, the minimum of them is still 4. In the second example one of the possible strings is "aabbccdda". In the third example at least one letter won't appear in the string, thus, the minimum of values f_i is always 0. Submitted Solution: ``` from collections import deque import bisect #n, k = map(int,input().split()) #s = input() n=200000 k=12 s = "?"*200000 maxconseq = [[0 for j in range(k)] for i in range(n+1)] for i in range(n): if s[i]=='?': for j in range(k): maxconseq[i][j] = maxconseq[i-1][j] + 1 else: j = ord(s[i])-97 maxconseq[i][j] = maxconseq[i-1][j] + 1 #print(maxconseq) def judge(needed): minstate = [2147483647]*(1<<k) minstate[0] = -1 effect = [[] for i in range(k)] for i in range(n): for j in range(k): if maxconseq[i][j]>=needed: effect[j].append(i) for state in range(1<<k): for j in range(k): if (1<<j) & state==0: continue loc = bisect.bisect_left(effect[j], minstate[state-(1<<j)] + needed) if loc == len(effect[j]): continue minstate[state] = min(minstate[state], effect[j][loc]) if minstate[-1]<n: return True return False front = 0 rear = n//k+1 while front < rear: mid = (front+rear)//2 flag = judge(mid) print(mid,flag) if flag: front = mid + 1 else: rear = mid print(front-1) ```
instruction
0
91,183
0
182,366
No
output
1
91,183
0
182,367
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a string s of length n. Each character is either one of the first k lowercase Latin letters or a question mark. You are asked to replace every question mark with one of the first k lowercase Latin letters in such a way that the following value is maximized. Let f_i be the maximum length substring of string s, which consists entirely of the i-th Latin letter. A substring of a string is a contiguous subsequence of that string. If the i-th letter doesn't appear in a string, then f_i is equal to 0. The value of a string s is the minimum value among f_i for all i from 1 to k. What is the maximum value the string can have? Input The first line contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 17) — the length of the string and the number of first Latin letters used. The second line contains a string s, consisting of n characters. Each character is either one of the first k lowercase Latin letters or a question mark. Output Print a single integer — the maximum value of the string after every question mark is replaced with one of the first k lowercase Latin letters. Examples Input 10 2 a??ab????b Output 4 Input 9 4 ????????? Output 2 Input 2 3 ?? Output 0 Input 15 3 ??b?babbc??b?aa Output 3 Input 4 4 cabd Output 1 Note In the first example the question marks can be replaced in the following way: "aaaababbbb". f_1 = 4, f_2 = 4, thus the answer is 4. Replacing it like this is also possible: "aaaabbbbbb". That way f_1 = 4, f_2 = 6, however, the minimum of them is still 4. In the second example one of the possible strings is "aabbccdda". In the third example at least one letter won't appear in the string, thus, the minimum of values f_i is always 0. Submitted Solution: ``` import io,os input = io.BytesIO(os.read(0, os.fstat(0).st_size)).readline from collections import deque n, k = map(int,input().split()) s = input() def judge(needed): inf = 2147483647 minstate = [inf]*(1<<k) minstate[0] = 0 effect = [[inf]*(n+1) for j in range(k)] for j in range(k): accu = 0 index = inf for i in range(n)[::-1]: if s[i]==ord('?') or s[i]==97+j: accu += 1 else: accu = 1 if accu>=needed: index = i + needed effect[j][i] = index # print(effect) for state in range(1,1<<k): minimum = minstate[state] for j in range(k): if (1<<j) & state==0: continue index = minstate[state^(1<<j)] if index<n: minimum = min(minimum, effect[j][index]) minstate[state] = minimum # print(minstate) if minstate[-1]<=n: return True return False front = 0 rear = n//k+1 while front < rear: mid = (front+rear)//2 flag = judge(mid) # print(mid,flag) if flag: front = mid + 1 else: rear = mid print(front-1) ```
instruction
0
91,184
0
182,368
No
output
1
91,184
0
182,369
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a string s of length n. Each character is either one of the first k lowercase Latin letters or a question mark. You are asked to replace every question mark with one of the first k lowercase Latin letters in such a way that the following value is maximized. Let f_i be the maximum length substring of string s, which consists entirely of the i-th Latin letter. A substring of a string is a contiguous subsequence of that string. If the i-th letter doesn't appear in a string, then f_i is equal to 0. The value of a string s is the minimum value among f_i for all i from 1 to k. What is the maximum value the string can have? Input The first line contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 17) — the length of the string and the number of first Latin letters used. The second line contains a string s, consisting of n characters. Each character is either one of the first k lowercase Latin letters or a question mark. Output Print a single integer — the maximum value of the string after every question mark is replaced with one of the first k lowercase Latin letters. Examples Input 10 2 a??ab????b Output 4 Input 9 4 ????????? Output 2 Input 2 3 ?? Output 0 Input 15 3 ??b?babbc??b?aa Output 3 Input 4 4 cabd Output 1 Note In the first example the question marks can be replaced in the following way: "aaaababbbb". f_1 = 4, f_2 = 4, thus the answer is 4. Replacing it like this is also possible: "aaaabbbbbb". That way f_1 = 4, f_2 = 6, however, the minimum of them is still 4. In the second example one of the possible strings is "aabbccdda". In the third example at least one letter won't appear in the string, thus, the minimum of values f_i is always 0. Submitted Solution: ``` from collections import deque import bisect #n, k = map(int,input().split()) #s = input() n=200000 k=10 s = "?"*200000 maxconseq = [[0 for j in range(k)] for i in range(n+1)] for i in range(n): if s[i]=='?': for j in range(k): maxconseq[i][j] = maxconseq[i-1][j] + 1 else: j = ord(s[i])-97 maxconseq[i][j] = maxconseq[i-1][j] + 1 #print(maxconseq) def judge(needed): minstate = [2147483647]*(1<<k) minstate[0] = -1 effect = [[] for i in range(k)] for i in range(n): for j in range(k): if maxconseq[i][j]>=needed: effect[j].append(i) for state in range(1<<k): for j in range(k): if (1<<j) & state==0: continue loc = bisect.bisect_left(effect[j], minstate[state-(1<<j)] + needed) if loc == len(effect[j]): continue minstate[state] = min(minstate[state], effect[j][loc]) if minstate[-1]<n: return True return False front = 0 rear = n//k+1 while front < rear: mid = (front+rear)//2 flag = judge(mid) print(mid,flag) if flag: front = mid + 1 else: rear = mid print(front-1) ```
instruction
0
91,185
0
182,370
No
output
1
91,185
0
182,371
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,311
0
182,622
Tags: greedy, sortings Correct Solution: ``` n=int(input()) l=sorted([int(i) for i in input().split()],reverse=True) l1=[0]*n l1[0]=l[0] s=l[0] for i in range(1,n): k=min(l[i],l1[i-1]-1) s+=k l1[i]=k if(k==0): break print(s) ```
output
1
91,311
0
182,623
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,312
0
182,624
Tags: greedy, sortings Correct Solution: ``` n=int(input()) l=[int(x) for x in input().split()] l.sort() ans=0 for i in range(n): val=l[i] while (val>0) and val in l[:i]: val-=1 l[i]=val ans+=val print(ans) ```
output
1
91,312
0
182,625
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,313
0
182,626
Tags: greedy, sortings Correct Solution: ``` """ B. Making a String codeforces.com """ _, nums = input(), [int(x) for x in input().split(' ')] nums.sort() nums.reverse() result = nums[0] prev = nums[0] for n in nums[1:]: n = prev-1 if n >= prev else n result += n prev = n if n == 0: break print (result) ```
output
1
91,313
0
182,627
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,314
0
182,628
Tags: greedy, sortings Correct Solution: ``` n = int(input()) l = list(map(int,input().split())) l.sort(reverse = 1) for i in range(1, n): if l[i] >= l[i-1]: l[i] = l[i-1]-1 if l[i] < 0: l[i] = 0 print(sum(l)) ```
output
1
91,314
0
182,629
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,315
0
182,630
Tags: greedy, sortings Correct Solution: ``` def main(): n = int(input()) a = [int(x) for x in input().split()] print(solver(a)) def solver(L): L.sort(reverse = True) total = 0 current = L[0] + 1 for i in range(len(L)): if L[i] >= current: current -= 1 if current <= 0: break else: current = L[i] total += current return total #L1 = [2, 5, 5] #print(solver(L1)) #L1 = [1, 1, 2, 2, 2] #print(solver(L1)) main() ```
output
1
91,315
0
182,631
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,316
0
182,632
Tags: greedy, sortings Correct Solution: ``` n = int(input()) ai = list(map(int,input().split())) ai.sort() ai.reverse() last_num = ai[0]+1 ans = 0 for num in ai: if last_num == 0: break if num >= last_num: last_num -= 1 else: last_num = num ans += last_num print(ans) ```
output
1
91,316
0
182,633
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,317
0
182,634
Tags: greedy, sortings Correct Solution: ``` N = int(input()) ans = 0 used = set() for c in sorted([int(x) for x in input().split()], reverse=True): while c > 0 and c in used: c -= 1 ans += c used.add(c) print(ans) ```
output
1
91,317
0
182,635
Provide tags and a correct Python 3 solution for this coding contest problem. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
instruction
0
91,318
0
182,636
Tags: greedy, sortings Correct Solution: ``` def make_s(lst): while True: lst.sort() for i in range(len(lst) - 1): if lst[i] == lst[i + 1]: lst[i] -= 1 break else: break return sum([x for x in lst if x > 0]) n = int(input()) a = [int(i) for i in input().split()] print(make_s(a)) ```
output
1
91,318
0
182,637
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` n = int(input()) data = list(map(int, input().split())) answer = 0 for i in range(n): if data.count(data[i]) == 1: answer += data[i] else: while data[i] > 0: if data.count(data[i]) == 1: answer += data[i] break else: data[i] -= 1 print(answer) ```
instruction
0
91,319
0
182,638
Yes
output
1
91,319
0
182,639
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` n = int(input()) A = list(map(int, input().split())) A.sort(reverse=True) ans = [A[0]] for i in range(1, n): if A[i] < ans[-1]: ans.append(A[i]) else: ans.append(max(0, ans[-1] - 1)) print(sum(ans)) ```
instruction
0
91,320
0
182,640
Yes
output
1
91,320
0
182,641
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` n = int(input()) l = list(map(int, input().split())) l = sorted(l)[-1::-1] for i in range(1, n): if l[i] >= l[i-1]: l[i] = l[i-1] - 1 if l[i] < 0: l[i] = 0 print(sum(l)) ```
instruction
0
91,321
0
182,642
Yes
output
1
91,321
0
182,643
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` def main(): n = int(input()) l = list(map(int, input().split())) l.sort() for i in range(1, n): while l.index(l[i]) != i: l[i] -= 1 answer = 0 for e in l: if e > 0: answer += e print(answer) if __name__ == "__main__": main() ```
instruction
0
91,322
0
182,644
Yes
output
1
91,322
0
182,645
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ```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erfection is achieved not when there is nothing more to add, but rather when there is nothing more to take away. """ import sys input = sys.stdin.readline # from bisect import bisect_left as lower_bound; # from bisect import bisect_right as upper_bound; # from math import ceil, factorial; def ceil(x): if x != int(x): x = int(x) + 1 return x def factorial(x, m): val = 1 while x>0: val = (val * x) % m x -= 1 return val def fact(x): val = 1 while x > 0: val *= x x -= 1 return val # swap_array function def swaparr(arr, a,b): temp = arr[a]; arr[a] = arr[b]; arr[b] = temp; ## gcd function def gcd(a,b): if b == 0: return a; return gcd(b, a % b); ## nCr function efficient using Binomial Cofficient def nCr(n, k): if k > n: return 0 if(k > n - k): k = n - k res = 1 for i in range(k): res = res * (n - i) res = res / (i + 1) return int(res) ## upper bound function code -- such that e in a[:i] e < x; def upper_bound(a, x, lo=0, hi = None): if hi == None: hi = len(a); while lo < hi: mid = (lo+hi)//2; if a[mid] < x: lo = mid+1; else: hi = mid; return lo; ## prime factorization def primefs(n): ## if n == 1 ## calculating primes primes = {} while(n%2 == 0 and n > 0): primes[2] = primes.get(2, 0) + 1 n = n//2 for i in range(3, int(n**0.5)+2, 2): while(n%i == 0 and n > 0): primes[i] = primes.get(i, 0) + 1 n = n//i if n > 2: primes[n] = primes.get(n, 0) + 1 ## prime factoriazation of n is stored in dictionary ## primes and can be accesed. O(sqrt n) return primes ## MODULAR EXPONENTIATION FUNCTION def power(x, y, p): res = 1 x = x % p if (x == 0) : return 0 while (y > 0) : if ((y & 1) == 1) : res = (res * x) % p y = y >> 1 x = (x * x) % p return res ## DISJOINT SET UNINON FUNCTIONS def swap(a,b): temp = a a = b b = temp return a,b; # find function with path compression included (recursive) # def find(x, link): # if link[x] == x: # return x # link[x] = find(link[x], link); # return link[x]; # find function with path compression (ITERATIVE) def find(x, link): p = x; while( p != link[p]): p = link[p]; while( x != p): nex = link[x]; link[x] = p; x = nex; return p; # the union function which makes union(x,y) # of two nodes x and y def union(x, y, link, size): x = find(x, link) y = find(y, link) if size[x] < size[y]: x,y = swap(x,y) if x != y: size[x] += size[y] link[y] = x ## returns an array of boolean if primes or not USING SIEVE OF ERATOSTHANES def sieve(n): prime = [True for i in range(n+1)] prime[0], prime[1] = False, False p = 2 while (p * p <= n): if (prime[p] == True): for i in range(p * p, n+1, p): prime[i] = False p += 1 return prime #### PRIME FACTORIZATION IN O(log n) using Sieve #### MAXN = int(1e5 + 5) def spf_sieve(): spf[1] = 1; for i in range(2, MAXN): spf[i] = i; for i in range(4, MAXN, 2): spf[i] = 2; for i in range(3, ceil(MAXN ** 0.5), 2): if spf[i] == i: for j in range(i*i, MAXN, i): if spf[j] == j: spf[j] = i; ## function for storing smallest prime factors (spf) in the array ################## un-comment below 2 lines when using factorization ################# spf = [0 for i in range(MAXN)] # spf_sieve(); def factoriazation(x): res = [] for i in range(2, int(x ** 0.5) + 1): while x % i == 0: res.append(i) x //= i if x != 1: res.append(x) return res ## this function is useful for multiple queries only, o/w use ## primefs function above. complexity O(log n) ## taking integer array input def int_array(): return list(map(int, input().strip().split())); def float_array(): return list(map(float, input().strip().split())); ## taking string array input def str_array(): return input().strip().split(); #defining a couple constants MOD = int(1e9)+7; CMOD = 998244353; INF = float('inf'); NINF = -float('inf'); ################### ---------------- TEMPLATE ENDS HERE ---------------- ################### from itertools import permutations import math from bisect import bisect_left def solve(): n = int(input()) a = sorted(list(map(int,input().split())), reverse = True) for i in range(1, n): if a[i] == a[i - 1]: a[i] = a[i - 1] - 1 print(sum(a)) if __name__ == '__main__': for _ in range(1): solve() # fin_time = datetime.now() # print("Execution time (for loop): ", (fin_time-init_time)) ```
instruction
0
91,323
0
182,646
No
output
1
91,323
0
182,647
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` l = int(input()) text = input().split() occ = [] text = list(map(int, text)) for item in text: if item in occ: occ.append(item - 1) if item not in occ: occ.append(item) sum = 0 for item in occ: sum += item print(sum) # 1496342017597 ```
instruction
0
91,324
0
182,648
No
output
1
91,324
0
182,649
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` n = int(input()) a = sorted(list(map(int, input().split())), reverse=True) ans = a[0] b = a[:] for i in range(1, n): if a[i] == a[i - 1]: b[i] = b[i - 1] - 1 ans += b[i] print(ans) ```
instruction
0
91,325
0
182,650
No
output
1
91,325
0
182,651
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given an alphabet consisting of n letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: * the i-th letter occurs in the string no more than ai times; * the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once. Input The first line of the input contains a single integer n (2 ≤ n ≤ 26) — the number of letters in the alphabet. The next line contains n integers ai (1 ≤ ai ≤ 109) — i-th of these integers gives the limitation on the number of occurrences of the i-th character in the string. Output Print a single integer — the maximum length of the string that meets all the requirements. Examples Input 3 2 5 5 Output 11 Input 3 1 1 2 Output 3 Note For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc". Submitted Solution: ``` import math def is_prime(n): if n==1: return False for i in range(2,int(math.sqrt(n))+1): if n%i==0: return False return True def inp(n): ls=list(map(int,input().split())) return ls def ans(ls): flag = [0] * t for i in range(t): k = 0 for j in range(t): if i != j and ls[i] == ls[j] and flag[i] == 0: flag[j] += 1 + k k += 1 #print(flag) for i in range(t): ls[i] = ls[i] - flag[i] t=int(input()) ls=inp(t) while(len(ls)!=len(set(ls))): ans(ls) print(sum(ls)) ```
instruction
0
91,326
0
182,652
No
output
1
91,326
0
182,653
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,777
0
183,554
Tags: greedy Correct Solution: ``` n = int(input()) st = input().rstrip() newSt = [st[0]] p = 1 dele = 0 cmp = True brk = False while True: if p+1 > len(st): break if cmp: while newSt[-1] == st[p]: p += 1 dele += 1 if p+1 > len(st): brk = True break if brk: break newSt.append(st[p]) p += 1 cmp = False else: newSt.append(st[p]) p += 1 cmp = True if len(newSt)%2 == 1: newSt.pop() dele += 1 print(dele) print(*newSt, sep='') ```
output
1
91,777
0
183,555
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,778
0
183,556
Tags: greedy Correct Solution: ``` n=int(input()) s=input() l=[] for i in range(0,n): if(len(l)%2==0 or s[i]!=l[-1]): l.append(s[i]) #print(l) if(len(l)%2!=0): l.pop() print(n-len(l)) print("".join(l)) else: print(n-len(l)) print("".join(l)) ```
output
1
91,778
0
183,557
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,779
0
183,558
Tags: greedy Correct Solution: ``` N = int(input()) S = input() ans = 0 res = "" i = 0 while i < N: if i < N - 1 and S[i] != S[i + 1]: res += S[i] res += S[i + 1] i += 2 elif i < N - 2 and S[i + 1] != S[i + 2]: res += S[i + 1] res += S[i + 2] ans += 1 i += 3 else: ans += 1 i += 1 print(ans) print(res) ```
output
1
91,779
0
183,559
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,780
0
183,560
Tags: greedy Correct Solution: ``` def fastio(): import sys from io import StringIO from atexit import register global input sys.stdin = StringIO(sys.stdin.read()) input = lambda : sys.stdin.readline().rstrip('\r\n') sys.stdout = StringIO() register(lambda : sys.__stdout__.write(sys.stdout.getvalue())) fastio() MOD = 10**9 + 7 I = lambda:list(map(int,input().split())) n, = I() s = input() l = [] l.append(s[0]) f = 0 m = [s[-1]] for i in s[1:]: if f: f = 0 l.append(i) elif l[-1] != i: l.append(i) f = 1 f = 0 for i in s[::-1][1:]: if f: f = 0 m.append(i) elif m[-1] != i: m.append(i) f = 1 a = len(l) b = len(m) m = list(reversed(m)) if a & 1: a -= 1 l = l[:-1] if b & 1: b -= 1 m = m[:-1] a = len(l) b = len(m) if a >= b: print(n - a) print(''.join(l)) else: print(n - b) print(''.join(m)) # v = [0]*n # u = [0]*n ```
output
1
91,780
0
183,561
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,781
0
183,562
Tags: greedy Correct Solution: ``` n = int(input()) s = input() ans = [] ansn = 0 for i in range(len(s)): if not ansn % 2 or s[i] != s[i - 1]: ans.append(s[i]) ansn += 1 if ansn % 2: ansn -= 1 ans.pop() print(n - ansn) print(''.join(ans)) ```
output
1
91,781
0
183,563
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,782
0
183,564
Tags: greedy Correct Solution: ``` n=int(input()) s=[] i=0 j=1 a=input() while j<n: if a[i]==a[j]: j+=1 else: s+=a[i]+a[j] i=j+1 j+=2 print(n-len(s)) print("".join(s)) ```
output
1
91,782
0
183,565
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,783
0
183,566
Tags: greedy Correct Solution: ``` num=int(input()) st=input() res=[] for i in range(len(st)): if len(res)%2==0 or res[-1]!=st[i]: res.append(st[i]) if len(res)%2==1: res.pop() print(num-len(res)) print(''.join(map(str,res))) ```
output
1
91,783
0
183,567
Provide tags and a correct Python 3 solution for this coding contest problem. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3
instruction
0
91,784
0
183,568
Tags: greedy Correct Solution: ``` """ NTC here """ from sys import setcheckinterval,stdin setcheckinterval(1000) #print("Case #{}: {} {}".format(i, n + m, n * m)) iin=lambda :int(stdin.readline()) lin=lambda :list(map(int,stdin.readline().split())) n=iin() a=input() ch=0 ans=[] dlt=0 i=0 while i<n: if ch%2==0: #print(ch,a[i],i) try: if a[i]!=a[i+1]: ch+=1 ans.append(a[i]) else: dlt+=1 except: if ch and ans[-1]!=a[i]:ans.append(a[i]) else:dlt+=1 else: ch+=1 ans.append(a[i]) i+=1 if len(ans)%2: dlt+=1 ans.pop() print(dlt) print(''.join(ans)) ```
output
1
91,784
0
183,569
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` def go(): n = int(input()) a = [i for i in input()] if n == 1: return '1\n' i = 1 while i < n: if a[i] == a[i - 1]: a[i - 1] = None i += 1 else: i += 2 a = ''.join(i for i in a if i is not None) if len(a) % 2 == 1: a = a[:-1] return '{}\n{}'.format(n - len(a), a) print(go()) ```
instruction
0
91,785
0
183,570
Yes
output
1
91,785
0
183,571
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` n = int(input()) i=0 a = input() minus = 0 ans='' while(i<n-1): if a[i]==a[i+1]: i+=1 minus+=1 else: # print(i, a[i], a[i+1]) ans += (a[i] + a[i + 1]) i += 2 # print('--->',ans) if i ==n-1: ans+=a[-1] if (n-minus)%2==1: minus+=1 ans=ans[:-1] if minus!=n: print(minus) print(ans) else:print(minus) ```
instruction
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183,572
Yes
output
1
91,786
0
183,573
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` from collections import defaultdict as ddic, Counter, deque from itertools import permutations def ipt(): return int(input()) def iptl(): return list(map(int, input().split())) MOD = 10 ** 9 + 7 def main(): N = ipt() S = input() ans = [] for x in S: if not ans or len(ans) % 2 == 0 or ans[-1] != x: ans.append(x) if len(ans) % 2: ans.pop() ans1 = N - len(ans), "".join(ans) print(ans1[0]) print(ans1[1]) if __name__ == '__main__': main() ```
instruction
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0
183,574
Yes
output
1
91,787
0
183,575
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` n = int(input()) a = list(input()) i = 0 k = 0 b = [] while 2*i+k<n-1: if a[2*i+k] == a[2*i+k+1]: k+=1 else: b.append(a[2*i+k]) b.append(a[2*i+k+1]) i+=1 print(k+((n-k)%2)) print(*b, sep='') ```
instruction
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0
183,576
Yes
output
1
91,788
0
183,577
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` n=int(input()) s=input().rstrip() x=list(s) D=0; if len(x)%2==0: if len(x)%2==0: l=[] q=[] i=0; while(i<len(x)-1): if x[i]==x[i+1]: i+=1; D+=1; else: l.append(x[i]) l.append(x[i+1]) q.append(i) q.append(i+1) i+=2; if len(q)==0 or q[len(q)-1]!=(n-1): l.append(x[len(x)-1]) if len(l)>1 and l[len(l)-1]==l[len(l)-2]: del(l[len(l)-1]) D+=1; if len(l)%2!=0: D+=1; del(l[len(l)-1]) print(D) if len(l)!=0: print(''.join(l)) else: print() else: if n==1: print(0) print(s) else: D=0; l=[] q=[] i=0; while(i<len(x)-1): if x[i]==x[i+1]: i+=1; D+=1; else: l.append(x[i]) l.append(x[i+1]) q.append(i) q.append(i+1) i+=2; if len(q)==0 or q[len(q)-1]!=(n-1): l.append(x[len(x)-1]) if len(l)>1 and l[len(l)-1]==l[len(l)-2]: del(l[len(l)-1]) D+=1; if len(l)%2!=0: D+=1; del(l[len(l)-1]) print(D) if len(l)!=0: print(''.join(l)) else: print() ```
instruction
0
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0
183,578
No
output
1
91,789
0
183,579
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` import sys n = int(sys.stdin.readline()) arr = list(sys.stdin.readline().rstrip()) i = 0 check = [True] * n while i < n: if i % 2 == 0: j = i + 1 while j < n: if arr[j] != arr[i]: break check[j] = False j += 1 i = j else: i += 1 cnt = 0 for i in range(n): if check[i]: cnt += 1 if cnt % 2 == 0: temp = 0 for i in range(n): if not check[i]: temp += 1 ans = [] for i in range(n): if check[i]: ans.append(arr[i]) print(temp) print(''.join(ans)) else: for i in range(n): if check[i]: check[i] = False break temp = 0 for i in range(n): if not check[i]: temp += 1 ans = [] for i in range(n): if check[i]: ans.append(arr[i]) print(temp) print(''.join(ans)) ```
instruction
0
91,790
0
183,580
No
output
1
91,790
0
183,581
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` n=int(input()) string=list(input()) m=n ex=0 if(n%2!=0): m-=1 ex+=1 i=0 flag=0 while i<(m-1): if(string[i]==string[i+1]): string[i]='-' flag=1 else: i+=1 if(flag==1): flag=0 m-=1 ex+=1 i+=1 count=0 newstr=[] for i in range(n-ex): if(string[i]!='-'): newstr.append(string[i]) count+=1 print(n-count) print(''.join(newstr)) ```
instruction
0
91,791
0
183,582
No
output
1
91,791
0
183,583
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good. You are given a string s, you have to delete minimum number of characters from this string so that it becomes good. Input The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s. The second line contains the string s, consisting of exactly n lowercase Latin letters. Output In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good. In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all. Examples Input 4 good Output 0 good Input 4 aabc Output 2 ab Input 3 aaa Output 3 Submitted Solution: ``` n = int(input()) s = input() def cal(s): n = len(s) ps1 = [0] * (n) ps2 = [0] * (n) cnt1, cnt2 = 0, 0 for i in range(1, n): if i & 1: cnt1 += s[i] == s[i - 1] else: cnt2 += s[i] == s[i - 1] ps1[i] = cnt1 ps2[i] = cnt2 p, mn = -1, 1e9 for i in range(n): tmp = 0 if i < n - 1: tmp += ps2[n - 1] - ps2[i + 1] if i: tmp += ps1[i - 1] if i & 1: tmp += s[i - 1] == s[i + 1] if tmp < mn: p = i mn = tmp ns = "" for i in range(n): if i != p: ns += s[i] return ns def cal2(s): n = len(s) ns = "" for i in range(0, n, 2): if s[i] != s[i + 1]: ns += s[i] + s[i + 1] return ns if n & 1: s = cal(s) s = cal2(s) print(n - len(s)) print(s) ```
instruction
0
91,792
0
183,584
No
output
1
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0
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a string t and n strings s_1, s_2, ..., s_n. All strings consist of lowercase Latin letters. Let f(t, s) be the number of occurences of string s in string t. For example, f('aaabacaa', 'aa') = 3, and f('ababa', 'aba') = 2. Calculate the value of ∑_{i=1}^{n} ∑_{j=1}^{n} f(t, s_i + s_j), where s + t is the concatenation of strings s and t. Note that if there are two pairs i_1, j_1 and i_2, j_2 such that s_{i_1} + s_{j_1} = s_{i_2} + s_{j_2}, you should include both f(t, s_{i_1} + s_{j_1}) and f(t, s_{i_2} + s_{j_2}) in answer. Input The first line contains string t (1 ≤ |t| ≤ 2 ⋅ 10^5). The second line contains integer n (1 ≤ n ≤ 2 ⋅ 10^5). Each of next n lines contains string s_i (1 ≤ |s_i| ≤ 2 ⋅ 10^5). It is guaranteed that ∑_{i=1}^{n} |s_i| ≤ 2 ⋅ 10^5. All strings consist of lowercase English letters. Output Print one integer — the value of ∑_{i=1}^{n} ∑_{j=1}^{n} f(t, s_i + s_j). Examples Input aaabacaa 2 a aa Output 5 Input aaabacaa 4 a a a b Output 33
instruction
0
91,794
0
183,588
Tags: brute force, string suffix structures, strings Correct Solution: ``` class Node(object): def __init__(self): super(Node, self).__init__() self.next = [-1] * 26 self.trans = [] self.matches = 0 self.leaf = 0 self.link = 0 class AhoCorasick(object): def __init__(self): super(AhoCorasick, self).__init__() self.T = [Node()] self.T[0].link = 0 def insert_trie(self, s): v = 0 for i in range(len(s)): c = ord(s[i]) - ord('a') if(self.T[v].next[c] == -1): self.T[v].trans.append(c) self.T[v].next[c] = len(self.T) self.T.append(Node()) v = self.T[v].next[c] self.T[v].leaf += 1 self.T[v].matches += 1 def set_suffix_link(self, S): Q = [] for j in range(len(S)): Q.append((j, 0, 0, 0)) #string index, index in string, state, suff state, i = 0 while(i < len(Q)): j,ind,v,suff = Q[i] i += 1 c = ord(S[j][ind]) - ord('a') if(ind>0): while(suff>0 and self.T[suff].next[c]==-1): suff = self.T[suff].link if(self.T[suff].next[c] != -1): suff = self.T[suff].next[c] v = self.T[v].next[c] self.T[v].link = suff if(ind+1 < len(S[j])): Q.append((j,ind+1,v,suff)) def set_matches(self): i = 0 Q = [0] while(i < len(Q)): v = Q[i] self.T[v].matches = self.T[v].leaf + self.T[self.T[v].link].matches for c in self.T[v].trans: Q.append(self.T[v].next[c]) i += 1 def build(self, S): for i in range(len(S)): self.insert_trie(S[i]) self.set_suffix_link(S) #self.printTree() self.set_matches() def get(self, s): v = 0 matches = [] for i in range(len(s)): c = ord(s[i]) - ord('a') while(v>0 and self.T[v].next[c] == -1): v = self.T[v].link if(self.T[v].next[c] != -1): v = self.T[v].next[c] matches.append(self.T[v].matches) return matches def printTree(self): for i in range(len(self.T)): print(str(i)+" leaf:"+str(self.T[i].leaf)+" link:"+str(self.T[i].link)+" matches:"+str(self.T[i].matches)+" : " , end='') for j in range(26): print(" "+str(chr(j+ord('a')))+"-"+(str(self.T[i].next[j]) if (self.T[i].next[j]!=-1) else "_")+" ", end='') print() t = input() n = int(input()) patterns = [] patterns_rev = [] for i in range(n): s = input() patterns.append(s) patterns_rev.append(s[::-1]) t1 = AhoCorasick() t2 = AhoCorasick() t1.build(patterns) t2.build(patterns_rev) x1 = t1.get(t) x2 = t2.get(t[::-1])[::-1] #print(x1) #print(x2) ans = 0 for i in range(len(x1)-1): ans += x1[i] * x2[i+1] print(ans) ```
output
1
91,794
0
183,589
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a string t and n strings s_1, s_2, ..., s_n. All strings consist of lowercase Latin letters. Let f(t, s) be the number of occurences of string s in string t. For example, f('aaabacaa', 'aa') = 3, and f('ababa', 'aba') = 2. Calculate the value of ∑_{i=1}^{n} ∑_{j=1}^{n} f(t, s_i + s_j), where s + t is the concatenation of strings s and t. Note that if there are two pairs i_1, j_1 and i_2, j_2 such that s_{i_1} + s_{j_1} = s_{i_2} + s_{j_2}, you should include both f(t, s_{i_1} + s_{j_1}) and f(t, s_{i_2} + s_{j_2}) in answer. Input The first line contains string t (1 ≤ |t| ≤ 2 ⋅ 10^5). The second line contains integer n (1 ≤ n ≤ 2 ⋅ 10^5). Each of next n lines contains string s_i (1 ≤ |s_i| ≤ 2 ⋅ 10^5). It is guaranteed that ∑_{i=1}^{n} |s_i| ≤ 2 ⋅ 10^5. All strings consist of lowercase English letters. Output Print one integer — the value of ∑_{i=1}^{n} ∑_{j=1}^{n} f(t, s_i + s_j). Examples Input aaabacaa 2 a aa Output 5 Input aaabacaa 4 a a a b Output 33 Submitted Solution: ``` class Node(object): def __init__(self): super(Node, self).__init__() self.next = [-1] * 26 self.matches = 0 self.leaf = 0 self.link = 0 class AhoCorasick(object): def __init__(self): super(AhoCorasick, self).__init__() self.T = [Node()] self.T[0].link = 0 def insert_trie(self, s): v = 0 for i in range(len(s)): c = ord(s[i]) - ord('a') if(self.T[v].next[c] == -1): self.T[v].next[c] = len(self.T) self.T.append(Node()) v = self.T[v].next[c] self.T[v].leaf += 1 self.T[v].matches += 1 def set_suffix_link(self, s): v = 0 suff = 0 for i in range(len(s)): c = ord(s[i])-ord('a') if(i>0): while(suff > 0 and self.T[suff].next[c] == -1): suff = self.T[suff].link if(self.T[suff].next[c] != -1): suff = self.T[suff].next[c] v = self.T[v].next[c] self.T[v].link = suff self.T[v].matches = self.T[v].leaf + self.T[suff].matches def build(self, S): for i in range(len(S)): self.insert_trie(S[i]) for i in range(len(S)): self.set_suffix_link(S[i]) def get(self, s): v = 0 matches = [] for i in range(len(s)): c = ord(s[i]) - ord('a') while(v>0 and self.T[v].next[c] == -1): v = self.T[v].link if(self.T[v].next[c] != -1): v = self.T[v].next[c] #print(str(i) + " : " + str(v) + " : " + str(self.T[v].matches)) matches.append(self.T[v].matches) return matches def printTree(self): for i in range(len(self.T)): print(str(i)+" leaf:"+str(self.T[i].leaf)+" link:"+str(self.T[i].link)+" matches:"+str(self.T[i].matches)+" : " , end='') for j in range(26): print(" "+str(chr(j+ord('a')))+"-"+(str(self.T[i].next[j]) if (self.T[i].next[j]!=-1) else "_")+" ", end='') print() t = input() n = int(input()) patterns = [] patterns_rev = [] for i in range(n): s = input() patterns.append(s) patterns_rev.append(s[::-1]) t1 = AhoCorasick() t2 = AhoCorasick() t1.build(patterns) t2.build(patterns_rev) x1 = t1.get(t) x2 = t2.get(t[::-1])[::-1] ans = 0 for i in range(len(x1)-1): ans += x1[i] * x2[i+1] print(ans) ```
instruction
0
91,795
0
183,590
No
output
1
91,795
0
183,591
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,959
0
183,918
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` import sys, math import heapq from collections import deque input = sys.stdin.readline #input def ip(): return int(input()) def sp(): return str(input().rstrip()) def mip(): return map(int, input().split()) def msp(): return map(str, input().split()) def lmip(): return list(map(int, input().split())) def lmsp(): return list(map(str, input().split())) #gcd, lcm def gcd(x, y): while y: x, y = y, x % y return x def lcm(x, y): return x * y // gcd(x, y) #prime def isPrime(x): if x==1: return False for i in range(2, int(x**0.5)+1): if x%i==0: return False return True # Union Find # p = {i:i for i in range(1, n+1)} def find(x): if x == p[x]: return x q = find(p[x]) p[x] = q return q def union(x, y): global n x = find(x) y = find(y) if x != y: p[y] = x def getPow(a, x): ret =1 while x: if x&1: ret = (ret*a) % MOD a = (a*a)%MOD x>>=1 return ret def getInv(x): return getPow(x, MOD-2) def lowerBound(start, end, key): while start < end: mid = (start + end) // 2 if lst[mid] == key: end = mid elif key < lst[mid]: end = mid elif lst[mid] < key: start = mid + 1 return end def upperBound(start, end, key): while start < end: mid = (start + end) // 2 if lst[mid] == key: start = mid + 1 elif lst[mid] < key: start = mid + 1 elif key < lst[mid]: end = mid if end == len(lst): return end-1 return end ############### Main! ############### t = ip() while t: t -= 1 n=ip() a=sp() b=sp() c=sp() i,j,k=0,0,0 ans=[] while True: if i==2*n: if j>=k: for m in range (j,2*n): ans.append(b[m]) else: for m in range (k,2*n): ans.append(c[m]) break elif j==2*n: if i>=k: for m in range (i,2*n): ans.append(a[m]) else: for m in range (k,2*n): ans.append(c[m]) break elif k==2*n: if j>=i: for m in range (j,2*n): ans.append(b[m]) else: for m in range (i,2*n): ans.append(a[m]) break if a[i]==b[j]: ans.append(a[i]) i+=1 j+=1 elif b[j]==c[k]: ans.append(b[j]) j+=1 k+=1 else: ans.append(a[i]) i+=1 k+=1 print(*ans,sep='') ######## Priest W_NotFoundGD ######## ```
output
1
91,959
0
183,919
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,960
0
183,920
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` # by the authority of GOD author: manhar singh sachdev # import os,sys from io import BytesIO,IOBase def solve(n,ls): x,y = [i.count('0') for i in ls],[i.count('1')for i in ls] for i in range(3): for j in range(3): if i == j: continue if x[i] >= n and x[j] >= n: ans,b = [],0 for a in ls[i]: if a == '1': ans.append('1') continue while b != 2*n and ls[j][b] != '0': ans.append('1') b += 1 ans.append('0') if b != 2*n: b += 1 while b != 2*n: ans.append(ls[j][b]) b += 1 return ''.join(ans) if y[i] >= n and y[j] >= n: ans,b = [],0 for a in ls[i]: if a == '0': ans.append('0') continue while b != 2*n and ls[j][b] != '1': ans.append('0') b += 1 ans.append('1') if b != 2*n: b += 1 while b != 2*n: ans.append(ls[j][b]) b += 1 return ''.join(ans) def main(): for _ in range(int(input())): n = int(input()) ls = [input().strip() for _ in range(3)] print(solve(n,ls)) #Fast IO Region 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") if __name__ == '__main__': main() ```
output
1
91,960
0
183,921
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,961
0
183,922
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` #!/usr/bin/env python import os import sys from io import BytesIO, IOBase def main(): for _ in range(int(input())): n = int(input()) a = [] a.append(input()) a.append(input()) a.append(input()) zeroDominant = [] oneDominant = [] for k in range(3): cnt = 0 for i in range(2 * n): if a[k][i] == "1": cnt += 1 if cnt >= n: oneDominant.append(a[k]) else: zeroDominant.append(a[k]) if len(oneDominant) >= 2: n *= 2 ans = [] fIndex = 0 lIndex = 0 while fIndex < n or lIndex < n: if fIndex == n and lIndex < n: ans.append(oneDominant[1][lIndex]) lIndex += 1 elif lIndex == n and fIndex < n: ans.append(oneDominant[0][fIndex]) fIndex += 1 else: if oneDominant[0][fIndex] == oneDominant[1][lIndex]: ans.append(oneDominant[0][fIndex]) fIndex += 1 lIndex += 1 else: ans.append("0") if oneDominant[0][fIndex] == "0": fIndex += 1 else: lIndex += 1 print("".join(ans)) else: n *= 2 ans = [] fIndex = 0 lIndex = 0 while fIndex < n or lIndex < n: if fIndex == n and lIndex < n: ans.append(zeroDominant[1][lIndex]) lIndex += 1 elif lIndex == n and fIndex < n: ans.append(zeroDominant[0][fIndex]) fIndex += 1 else: if zeroDominant[0][fIndex] == zeroDominant[1][lIndex]: ans.append(zeroDominant[0][fIndex]) fIndex += 1 lIndex += 1 else: ans.append("1") if zeroDominant[0][fIndex] == "1": fIndex += 1 else: lIndex += 1 print("".join(ans)) # region fastio 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") # endregion if __name__ == "__main__": main() ```
output
1
91,961
0
183,923
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,962
0
183,924
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` from bisect import * from collections import * from math import gcd,ceil,sqrt,floor,inf from heapq import * from itertools import * from operator import add,mul,sub,xor,truediv,floordiv from functools import * #------------------------------------------------------------------------ import os import sys from io import BytesIO, IOBase # region fastio 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") #------------------------------------------------------------------------ def RL(): return map(int, sys.stdin.readline().rstrip().split()) def RLL(): return list(map(int, sys.stdin.readline().rstrip().split())) def N(): return int(input()) def A(n):return [0]*n def AI(n,x): return [x]*n def A2(n,m): return [[0]*m for i in range(n)] def G(n): return [[] for i in range(n)] def GP(it): return [[ch,len(list(g))] for ch,g in groupby(it)] #------------------------------------------------------------------------ from types import GeneratorType def bootstrap(f, stack=[]): def wrappedfunc(*args, **kwargs): if stack: return f(*args, **kwargs) else: to = f(*args, **kwargs) while True: if type(to) is GeneratorType: stack.append(to) to = next(to) else: stack.pop() if not stack: break to = stack[-1].send(to) return to return wrappedfunc mod=10**9+7 farr=[1] ifa=[] def fact(x,mod=0): if mod: while x>=len(farr): farr.append(farr[-1]*len(farr)%mod) else: while x>=len(farr): farr.append(farr[-1]*len(farr)) return farr[x] def ifact(x,mod): global ifa fact(x,mod) ifa.append(pow(farr[-1],mod-2,mod)) for i in range(x,0,-1): ifa.append(ifa[-1]*i%mod) ifa.reverse() def per(i,j,mod=0): if i<j: return 0 if not mod: return fact(i)//fact(i-j) return farr[i]*ifa[i-j]%mod def com(i,j,mod=0): if i<j: return 0 if not mod: return per(i,j)//fact(j) return per(i,j,mod)*ifa[j]%mod def catalan(n): return com(2*n,n)//(n+1) def isprime(n): for i in range(2,int(n**0.5)+1): if n%i==0: return False return True def floorsum(a,b,c,n):#sum((a*i+b)//c for i in range(n+1)) if a==0:return b//c*(n+1) if a>=c or b>=c: return floorsum(a%c,b%c,c,n)+b//c*(n+1)+a//c*n*(n+1)//2 m=(a*n+b)//c return n*m-floorsum(c,c-b-1,a,m-1) def inverse(a,m): a%=m if a<=1: return a return ((1-inverse(m,a)*m)//a)%m def lowbit(n): return n&-n class BIT: def __init__(self,arr): self.arr=arr self.n=len(arr)-1 def update(self,x,v): while x<=self.n: self.arr[x]+=v x+=x&-x def query(self,x): ans=0 while x: ans+=self.arr[x] x&=x-1 return ans class ST: def __init__(self,arr):#n!=0 n=len(arr) mx=n.bit_length()#取不到 self.st=[[0]*mx for i in range(n)] for i in range(n): self.st[i][0]=arr[i] for j in range(1,mx): for i in range(n-(1<<j)+1): self.st[i][j]=max(self.st[i][j-1],self.st[i+(1<<j-1)][j-1]) def query(self,l,r): if l>r:return -inf s=(r+1-l).bit_length()-1 return max(self.st[l][s],self.st[r-(1<<s)+1][s]) ''' class DSU:#容量+路径压缩 def __init__(self,n): self.c=[-1]*n def same(self,x,y): return self.find(x)==self.find(y) def find(self,x): if self.c[x]<0: return x self.c[x]=self.find(self.c[x]) return self.c[x] def union(self,u,v): u,v=self.find(u),self.find(v) if u==v: return False if self.c[u]>self.c[v]: u,v=v,u self.c[u]+=self.c[v] self.c[v]=u return True def size(self,x): return -self.c[self.find(x)]''' class UFS:#秩+路径 def __init__(self,n): self.parent=[i for i in range(n)] self.ranks=[0]*n def find(self,x): if x!=self.parent[x]: self.parent[x]=self.find(self.parent[x]) return self.parent[x] def union(self,u,v): pu,pv=self.find(u),self.find(v) if pu==pv: return False if self.ranks[pu]>=self.ranks[pv]: self.parent[pv]=pu if self.ranks[pv]==self.ranks[pu]: self.ranks[pu]+=1 else: self.parent[pu]=pv def Prime(n): c=0 prime=[] flag=[0]*(n+1) for i in range(2,n+1): if not flag[i]: prime.append(i) c+=1 for j in range(c): if i*prime[j]>n: break flag[i*prime[j]]=prime[j] if i%prime[j]==0: break return prime def dij(s,graph): d={} d[s]=0 heap=[(0,s)] seen=set() while heap: dis,u=heappop(heap) if u in seen: continue seen.add(u) for v,w in graph[u]: if v not in d or d[v]>d[u]+w: d[v]=d[u]+w heappush(heap,(d[v],v)) return d def bell(s,g):#bellman-Ford dis=AI(n,inf) dis[s]=0 for i in range(n-1): for u,v,w in edge: if dis[v]>dis[u]+w: dis[v]=dis[u]+w change=A(n) for i in range(n): for u,v,w in edge: if dis[v]>dis[u]+w: dis[v]=dis[u]+w change[v]=1 return dis def lcm(a,b): return a*b//gcd(a,b) def lis(nums): res=[] for k in nums: i=bisect.bisect_left(res,k) if i==len(res): res.append(k) else: res[i]=k return len(res) def RP(nums):#逆序对 n = len(nums) s=set(nums) d={} for i,k in enumerate(sorted(s),1): d[k]=i bi=BIT([0]*(len(s)+1)) ans=0 for i in range(n-1,-1,-1): ans+=bi.query(d[nums[i]]-1) bi.update(d[nums[i]],1) return ans class DLN: def __init__(self,val): self.val=val self.pre=None self.next=None def nb(i,j,n,m): for ni,nj in [[i+1,j],[i-1,j],[i,j-1],[i,j+1]]: if 0<=ni<n and 0<=nj<m: yield ni,nj def topo(n): q=deque() res=[] for i in range(1,n+1): if ind[i]==0: q.append(i) res.append(i) while q: u=q.popleft() for v in g[u]: ind[v]-=1 if ind[v]==0: q.append(v) res.append(v) return res @bootstrap def gdfs(r,p): for ch in g[r]: if ch!=p: yield gdfs(ch,r) yield None def cal(x): ans=0 for i in range(2*n): ans+=x[i]=='1' return ans def f(x,y,ch): ans=[] i=j=0 c=0 while True: while i<2*n and x[i]!=ch: ans.append(x[i]) i+=1 while j<2*n and y[j]!=ch: ans.append(y[j]) j+=1 ans.append(x[i]) i+=1 j+=1 c+=1 if c>=n: break ans=ans+x[i:]+y[j:] return ''.join(ans) t=N() for i in range(t): n=N() a=list(input()) b=list(input()) c=list(input()) ca=cal(a) cb=cal(b) cc=cal(c) res=[[a,ca],[b,cb],[c,cc]] res.sort(key=lambda x:x[1]) [a,ca],[b,cb],[c,cc]=res if cb>=n: ans=f(b,c,'1') else: ans=f(a,b,'0') print(ans) ''' sys.setrecursionlimit(200000) import threading threading.stack_size(10**8) t=threading.Thr ead(target=main) t.start() t.join() ''' ```
output
1
91,962
0
183,925
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,963
0
183,926
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` import sys input=sys.stdin.readline t=int(input()) for _ in range(t): n=int(input()) ans=[] s1=input() s2=input() s3=input() fincount=0 count10=0 for i in range(2*n): if s1[i]=='0': count10+=1 if count10>=n: fincount+=1 count20=0 for i in range(2*n): if s2[i]=='0': count20+=1 if count20>=n: fincount+=1 count30=0 for i in range(2*n): if s3[i]=='0': count30+=1 if count30>=n: fincount+=1 if fincount>=2: mode='0' unmode='1' else: mode='1' unmode='0' if mode=='0': if count10>=n and count20>=n: st1=s1 st2=s2 elif count10>=n and count30>=n: st1=s1 st2=s3 elif count20>=n and count30>=n: st1=s2 st2=s3 else: if count10<=n and count20<=n: st1=s1 st2=s2 elif count10<=n and count30<=n: st1=s1 st2=s3 elif count20<=n and count30<=n: st1=s2 st2=s3 pointer1=0 pointer2=0 while pointer1<2*n or pointer2<2*n: while pointer1<2*n and st1[pointer1]==unmode: pointer1+=1 ans.append(unmode) while pointer2<2*n and st2[pointer2]==unmode: pointer2+=1 ans.append(unmode) if pointer1>=2*n and pointer2>=2*n: break ans.append(mode) pointer1+=1 pointer2+=1 print(''.join(ans)) ```
output
1
91,963
0
183,927
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,964
0
183,928
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` import sys,os from io import BytesIO,IOBase mod = 10**9+7; Mod = 998244353; INF = float('inf') # input = lambda: sys.stdin.readline().rstrip("\r\n") # inp = lambda: list(map(int,sys.stdin.readline().rstrip("\r\n").split())) #______________________________________________________________________________________________________ # region fastio ''' 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) # endregion''' #______________________________________________________________________________________________________ input = lambda: sys.stdin.readline().rstrip("\r\n") inp = lambda: list(map(int,sys.stdin.readline().rstrip("\r\n").split())) # ______________________________________________________________________________________________________ # from math import * # from bisect import * # from heapq import * # from collections import defaultdict as dd # from collections import OrderedDict as odict # from collections import Counter as cc # from collections import deque # from itertools import groupby # sys.setrecursionlimit(2000+10) #this is must for dfs # ______________________________________________________________________________________________________ # segment tree for range minimum query # n = int(input()) # a = list(map(int,input().split())) # st = [float('inf') for i in range(4*len(a))] # def build(a,ind,start,end): # if start == end: # st[ind] = a[start] # else: # mid = (start+end)//2 # build(a,2*ind+1,start,mid) # build(a,2*ind+2,mid+1,end) # st[ind] = min(st[2*ind+1],st[2*ind+2]) # build(a,0,0,n-1) # def query(ind,l,r,start,end): # if start>r or end<l: # return float('inf') # if l<=start<=end<=r: # return st[ind] # mid = (start+end)//2 # return min(query(2*ind+1,l,r,start,mid),query(2*ind+2,l,r,mid+1,end)) # ______________________________________________________________________________________________________ # Checking prime in O(root(N)) # def isprime(n): # if (n % 2 == 0 and n > 2) or n == 1: return 0 # else: # s = int(n**(0.5)) + 1 # for i in range(3, s, 2): # if n % i == 0: # return 0 # return 1 # def lcm(a,b): # return (a*b)//gcd(a,b) # ______________________________________________________________________________________________________ # nCr under mod # def C(n,r,mod = 10**9+7): # if r>n: return 0 # if r>n-r: r = n-r # num = den = 1 # for i in range(r): # num = (num*(n-i))%mod # den = (den*(i+1))%mod # return (num*pow(den,mod-2,mod))%mod # def C(n,r): # if r>n: # return 0 # if r>n-r: # r = n-r # ans = 1 # for i in range(r): # ans = (ans*(n-i))//(i+1) # return ans # ______________________________________________________________________________________________________ # For smallest prime factor of a number # M = 2*10**5+10 # spf = [i for i in range(M)] # def spfs(M): # for i in range(2,M): # if spf[i]==i: # for j in range(i*i,M,i): # if spf[j]==j: # spf[j] = i # return # spfs(M) # ______________________________________________________________________________________________________ # def gtc(p): # print('Case #'+str(p)+': ',end='') # ______________________________________________________________________________________________________ tc = 1 tc = int(input()) for test in range(1,tc+1): n = int(input()) s1 = str(input()) s2 = str(input()) s3 = str(input()) o1 = s1.count('1');z1 = 2*n-o1 o2 = s2.count('1');z2 = 2*n-o2 o3 = s3.count('1');z3 = 2*n-o3 def solve(s1,s2,k): ans = [] i = 0 j = 0 n = len(s1) while(i<n and j<n): if s1[i]==s2[j]: ans.append(s1[i]) i+=1 j+=1 else: if s1[i]==k: ans.append(s2[j]) j+=1 else: ans.append(s1[i]) i+=1 while(i<n): ans.append(s1[i]) i+=1 while(j<n): ans.append(s2[j]) j+=1 # print(s1,s2,ans) return ''.join(ans)+'0'*((n//2)*3-len(ans)) if o1>=n and o2>=n: ans = solve(s1,s2,'1') elif o2>=n and o3>=n: ans = solve(s2,s3,'1') elif o1>=n and o3>=n: ans = solve(s1,s3,'1') elif z1>=n and z2>=n: ans = solve(s1,s2,'0') elif z2>=n and z3>=n: ans = solve(s2,s3,'0') else: ans = solve(s1,s3,'0') print(ans) ```
output
1
91,964
0
183,929
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,965
0
183,930
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` import sys from sys import stdin def solve(a,b,X): #print (a,b,X,file=sys.stderr) ans = [] ca = [a[i] for i in range(len(a))] cb = [b[i] for i in range(len(b))] while len(ca) > 0 or len(cb) > 0: if len(cb) == 0: ans.append(ca[-1]) del ca[-1] elif len(ca) == 0: ans.append(cb[-1]) del cb[-1] elif ca[-1] == cb[-1]: ans.append(ca[-1]) del ca[-1] del cb[-1] else: ans.append(X) if ca[-1] == X: del ca[-1] else: del cb[-1] while len(ans) < 3*n: ans.append("0") ans.reverse() return "".join(ans) tt = int(stdin.readline()) for loop in range(tt): n = int(stdin.readline()) s = [stdin.readline()[:-1] for i in range(3)] lis = [] for i in range(3): one = 0 zero = 0 for j in s[i]: if j == "0": zero += 1 else: one += 1 if one < zero: lis.append("1") else: lis.append("0") flag = True for i in range(3): for j in range(i): if lis[i] == lis[j] and flag: print (solve(s[i],s[j],lis[i])) flag = False ```
output
1
91,965
0
183,931
Provide tags and a correct Python 3 solution for this coding contest problem. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.
instruction
0
91,966
0
183,932
Tags: constructive algorithms, greedy, implementation, strings, two pointers Correct Solution: ``` import sys input = sys.stdin.readline def main(): n = int(input()) S1 = input().strip() S2 = input().strip() S3 = input().strip() for s1 in (S1, S2, S3): for s2 in (S1, S2, S3): if s1 == s2: continue z1 = s1.count("0") o1 = s1.count("1") z2 = s2.count("0") o2 = s2.count("1") mz = max(z1, z2) mo = max(o1, o2) if mz > n and mo > n: continue if mz <= n: cnt1 = [] cnt2 = [] bef = "0" cnt = 0 for s in s1: if s == "1": cnt1.append(cnt) cnt = 0 else: cnt += 1 bef = s if cnt: cnt1.append(cnt) bef = "0" cnt = 0 for s in s2: if s == "1": cnt2.append(cnt) cnt = 0 else: cnt += 1 bef = s if cnt: cnt2.append(cnt) if len(cnt1) > len(cnt2): cnt2 += [0] * (len(cnt1) - len(cnt2)) elif len(cnt1) < len(cnt2): cnt1 += [0] * (len(cnt2) - len(cnt1)) ans = [] for c1, c2 in zip(cnt1, cnt2): ans += ["0"] * max(c1, c2) ans += ["1"] ans.pop() if len(ans) < 3 * n: ans += ["1"] * (3 * n - len(ans)) print("".join(ans)) return elif mo <= n: cnt1 = [] cnt2 = [] bef = "1" cnt = 0 for s in s1: if s == "0": cnt1.append(cnt) cnt = 0 else: cnt += 1 bef = s if cnt: cnt1.append(cnt) bef = "1" cnt = 0 for s in s2: if s == "0": cnt2.append(cnt) cnt = 0 else: cnt += 1 bef = s if cnt: cnt2.append(cnt) if len(cnt1) > len(cnt2): cnt2 += [0] * (len(cnt1) - len(cnt2)) elif len(cnt1) < len(cnt2): cnt1 += [0] * (len(cnt2) - len(cnt1)) ans = [] for c1, c2 in zip(cnt1, cnt2): ans += ["1"] * max(c1, c2) ans += ["0"] ans.pop() if len(ans) < 3 * n: ans += ["0"] * (3 * n - len(ans)) print("".join(ans)) return for _ in range(int(input())): main() ```
output
1
91,966
0
183,933
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010. Submitted Solution: ``` # by the authority of GOD author: manhar singh sachdev # def some_random_function(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function5(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) import os,sys from io import BytesIO,IOBase def solve(n,ls): x,y = [i.count('0') for i in ls],[i.count('1')for i in ls] for i in range(3): for j in range(3): if i == j: continue if x[i] >= n and x[j] >= n: ans,b = [],0 for a in ls[i]: if a == '1': ans.append('1') continue while b != 2*n and ls[j][b] != '0': ans.append('1') b += 1 ans.append('0') if b != 2*n: b += 1 while b != 2*n: ans.append(ls[j][b]) b += 1 return ''.join(ans) if y[i] >= n and y[j] >= n: ans,b = [],0 for a in ls[i]: if a == '0': ans.append('0') continue while b != 2*n and ls[j][b] != '1': ans.append('0') b += 1 ans.append('1') if b != 2*n: b += 1 while b != 2*n: ans.append(ls[j][b]) b += 1 return ''.join(ans) def main(): for _ in range(int(input())): n = int(input()) ls = [input().strip() for _ in range(3)] print(solve(n,ls)) #Fast IO Region 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") def some_random_function1(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function2(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function3(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function4(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function6(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function7(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) def some_random_function8(): """due to the fast IO template, my code gets caught in plag check for no reason. That is why, I am making random functions""" x = 10 x *= 100 i_dont_know = x why_am_i_writing_this = x*x print(i_dont_know) print(why_am_i_writing_this) if __name__ == '__main__': main() ```
instruction
0
91,967
0
183,934
Yes
output
1
91,967
0
183,935
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010. Submitted Solution: ``` import sys input = sys.stdin.readline for f in range(int(input())): n=int(input()) s=[] for i in range(3): s.append(input()) s1=[] s0=[] for i in range(3): c0=0 for x in s[i]: if x=="0":c0+=1 s0.append(c0) s1.append(2*n-s0[-1]) for i in range(2): for j in range(i+1,3): if s0[i]>=n and s0[j]>=n: c1=i c2=j g="0" b="1" if s1[i]>=n and s1[j]>=n: c1=i c2=j g="1" b="0" i=j=0 while i<2*n or j<2*n: if i<2*n and s[c1][i]==b: i+=1 print(end=b) else: if j<2*n and s[c2][j]==b: j+=1 print(end=b) else: print(end=g) i+=1 j+=1 print() ```
instruction
0
91,968
0
183,936
Yes
output
1
91,968
0
183,937
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010. Submitted Solution: ``` tc = int(input()) for i in range(tc): n = int(input()) s = [input() for _ in range(3)] p = [0]*3 ans = "" while True: ones = [] oc = 0 zeroes = [] for i in range(3): if s[i][p[i]] == '1': ones.append(i) oc += 1 else: zeroes.append(i) if oc >= 2: print('1', end="") for i in ones: p[i] += 1 else: print('0', end="") for i in zeroes: p[i] += 1 if (p[0] == 2*n) or (p[1] == 2*n) or (p[2] == 2*n): break #pick the smallest left omg x = sorted(enumerate(p), key=lambda i:i[1]) print(s[x[1][0]][x[1][1]:]) #3 pointer trick in comments ```
instruction
0
91,969
0
183,938
Yes
output
1
91,969
0
183,939
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A bitstring is a string that contains only the characters 0 and 1. Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences. Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest. A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters. Input The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases. The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5). Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct. It is guaranteed that the sum of n across all test cases does not exceed 10^5. Output For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences. It can be proven that under the constraints of the problem, such a bitstring always exists. If there are multiple possible answers, you may output any of them. Example Input 2 1 00 11 01 3 011001 111010 010001 Output 010 011001010 Note In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required. In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010. Submitted Solution: ``` from sys import * input = stdin.readline def superstring(x,y,fx,n): ans = "" i,j = 0,0 while (i<2*n) and (j<2*n): if x[i]==y[j]: ans+=x[i] i+=1 j+=1 elif x[i]!=fx: ans+=x[i] i+=1 else: ans+=y[j] j+=1 return ans+x[i:]+y[j:] for _ in range(int(input())): n = int(input()) a,b,c = input().strip(),input().strip(),input().strip() one,zero = [],[] for i in [a,b,c]: if i.count("0")>=n: zero.append(i) else: one.append(i) currans = "" if len(zero)>len(one): currans = superstring(zero[0],zero[1],'0',n) else: currans = superstring(one[0],one[1],'1',n) print(currans.rjust(3*n,'0')) ```
instruction
0
91,970
0
183,940
Yes
output
1
91,970
0
183,941