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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp watched TV-show where k jury members one by one rated a participant by adding him a certain number of points (may be negative, i. e. points were subtracted). Initially the participant had some score, and each the marks were one by one added to his score. It is known that the i-th jury member gave ai points. Polycarp does not remember how many points the participant had before this k marks were given, but he remembers that among the scores announced after each of the k judges rated the participant there were n (n ≀ k) values b1, b2, ..., bn (it is guaranteed that all values bj are distinct). It is possible that Polycarp remembers not all of the scores announced, i. e. n < k. Note that the initial score wasn't announced. Your task is to determine the number of options for the score the participant could have before the judges rated the participant. Input The first line contains two integers k and n (1 ≀ n ≀ k ≀ 2 000) β€” the number of jury members and the number of scores Polycarp remembers. The second line contains k integers a1, a2, ..., ak ( - 2 000 ≀ ai ≀ 2 000) β€” jury's marks in chronological order. The third line contains n distinct integers b1, b2, ..., bn ( - 4 000 000 ≀ bj ≀ 4 000 000) β€” the values of points Polycarp remembers. Note that these values are not necessarily given in chronological order. Output Print the number of options for the score the participant could have before the judges rated the participant. If Polycarp messes something up and there is no options, print "0" (without quotes). Examples Input 4 1 -5 5 0 20 10 Output 3 Input 2 2 -2000 -2000 3998000 4000000 Output 1 Note The answer for the first example is 3 because initially the participant could have - 10, 10 or 15 points. In the second example there is only one correct initial score equaling to 4 002 000. Submitted Solution: ``` from collections import * import sys from math import pow # "". join(strings) def ri(): return int(input()) def rl(): return list(map(int, input().split())) k,n =rl() aa= rl() bb=rl() aa.sort() bb.sort() sums_aa = [0]*k sums_aa[0]=aa[0] for i in range(1,k): sums_aa[i]=aa[i]+sums_aa[i-1] ans=set([]) for i in range(n): for j in range(k): ans.add(bb[i]-sums_aa[j]) out=0 for d in ans: possible_b = set([]) for j in range(k): possible_b.add(d+sums_aa[j]) for j in range(n): if bb[j] not in possible_b: break else: out+=1 print(out) ```
instruction
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67,825
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135,650
No
output
1
67,825
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135,651
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp watched TV-show where k jury members one by one rated a participant by adding him a certain number of points (may be negative, i. e. points were subtracted). Initially the participant had some score, and each the marks were one by one added to his score. It is known that the i-th jury member gave ai points. Polycarp does not remember how many points the participant had before this k marks were given, but he remembers that among the scores announced after each of the k judges rated the participant there were n (n ≀ k) values b1, b2, ..., bn (it is guaranteed that all values bj are distinct). It is possible that Polycarp remembers not all of the scores announced, i. e. n < k. Note that the initial score wasn't announced. Your task is to determine the number of options for the score the participant could have before the judges rated the participant. Input The first line contains two integers k and n (1 ≀ n ≀ k ≀ 2 000) β€” the number of jury members and the number of scores Polycarp remembers. The second line contains k integers a1, a2, ..., ak ( - 2 000 ≀ ai ≀ 2 000) β€” jury's marks in chronological order. The third line contains n distinct integers b1, b2, ..., bn ( - 4 000 000 ≀ bj ≀ 4 000 000) β€” the values of points Polycarp remembers. Note that these values are not necessarily given in chronological order. Output Print the number of options for the score the participant could have before the judges rated the participant. If Polycarp messes something up and there is no options, print "0" (without quotes). Examples Input 4 1 -5 5 0 20 10 Output 3 Input 2 2 -2000 -2000 3998000 4000000 Output 1 Note The answer for the first example is 3 because initially the participant could have - 10, 10 or 15 points. In the second example there is only one correct initial score equaling to 4 002 000. Submitted Solution: ``` k,n = map(int,input().split(" ")) marks = [int(x) for x in input().split(" ")] poly_rem = [int(x) for x in input().split(" ")] possible_marks = [] def sumUntil(i): global marks return sum(marks[:i]) for i in range(k): getSum = sumUntil(i+1) pos = set() for x in range(len(poly_rem)): pos.add(poly_rem[x]-getSum) possible_marks.append(pos) result = set() if len(possible_marks) >= 2: result = possible_marks[0] for i in range(1,len(possible_marks)): result = result.intersection(possible_marks[i]) print(len(result)) ```
instruction
0
67,826
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135,652
No
output
1
67,826
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135,653
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp watched TV-show where k jury members one by one rated a participant by adding him a certain number of points (may be negative, i. e. points were subtracted). Initially the participant had some score, and each the marks were one by one added to his score. It is known that the i-th jury member gave ai points. Polycarp does not remember how many points the participant had before this k marks were given, but he remembers that among the scores announced after each of the k judges rated the participant there were n (n ≀ k) values b1, b2, ..., bn (it is guaranteed that all values bj are distinct). It is possible that Polycarp remembers not all of the scores announced, i. e. n < k. Note that the initial score wasn't announced. Your task is to determine the number of options for the score the participant could have before the judges rated the participant. Input The first line contains two integers k and n (1 ≀ n ≀ k ≀ 2 000) β€” the number of jury members and the number of scores Polycarp remembers. The second line contains k integers a1, a2, ..., ak ( - 2 000 ≀ ai ≀ 2 000) β€” jury's marks in chronological order. The third line contains n distinct integers b1, b2, ..., bn ( - 4 000 000 ≀ bj ≀ 4 000 000) β€” the values of points Polycarp remembers. Note that these values are not necessarily given in chronological order. Output Print the number of options for the score the participant could have before the judges rated the participant. If Polycarp messes something up and there is no options, print "0" (without quotes). Examples Input 4 1 -5 5 0 20 10 Output 3 Input 2 2 -2000 -2000 3998000 4000000 Output 1 Note The answer for the first example is 3 because initially the participant could have - 10, 10 or 15 points. In the second example there is only one correct initial score equaling to 4 002 000. Submitted Solution: ``` #!/usr/bin/python3 if __name__ == '__main__': k, n = map(int, input().split()) a = list(map(int, input().split())) b = list(map(int, input().split())) x = 0 sol1 = set() for ak in a: x += ak sol1.add(b[0] - x) for bk in b[1:]: x = 0 sol = set() for ak in a: x += ak sol.add(bk - ak) sol1 = sol1.intersection(sol) print(len(sol1)) ```
instruction
0
67,827
24
135,654
No
output
1
67,827
24
135,655
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp watched TV-show where k jury members one by one rated a participant by adding him a certain number of points (may be negative, i. e. points were subtracted). Initially the participant had some score, and each the marks were one by one added to his score. It is known that the i-th jury member gave ai points. Polycarp does not remember how many points the participant had before this k marks were given, but he remembers that among the scores announced after each of the k judges rated the participant there were n (n ≀ k) values b1, b2, ..., bn (it is guaranteed that all values bj are distinct). It is possible that Polycarp remembers not all of the scores announced, i. e. n < k. Note that the initial score wasn't announced. Your task is to determine the number of options for the score the participant could have before the judges rated the participant. Input The first line contains two integers k and n (1 ≀ n ≀ k ≀ 2 000) β€” the number of jury members and the number of scores Polycarp remembers. The second line contains k integers a1, a2, ..., ak ( - 2 000 ≀ ai ≀ 2 000) β€” jury's marks in chronological order. The third line contains n distinct integers b1, b2, ..., bn ( - 4 000 000 ≀ bj ≀ 4 000 000) β€” the values of points Polycarp remembers. Note that these values are not necessarily given in chronological order. Output Print the number of options for the score the participant could have before the judges rated the participant. If Polycarp messes something up and there is no options, print "0" (without quotes). Examples Input 4 1 -5 5 0 20 10 Output 3 Input 2 2 -2000 -2000 3998000 4000000 Output 1 Note The answer for the first example is 3 because initially the participant could have - 10, 10 or 15 points. In the second example there is only one correct initial score equaling to 4 002 000. Submitted Solution: ``` #!/usr/bin/env python3 def solve(): k, n = get([int]) A = get([int]) B = get([int]) Bset = set(B) s = list(itertools.accumulate(A)) print(s) valid = set() count = 0 for judge, current in itertools.product(B, s): score = judge - current s2 = set(score + i for i in s) if Bset <= s2: valid.add(score) return len(valid) _testcases = """ 4 1 -5 5 0 20 10 3 2 2 -2000 -2000 3998000 4000000 1 """.strip() # ======================= B O I L E R P L A T E ======================= # # Practicality beats purity import re import sys import math import heapq from heapq import heapify, heappop, heappush import bisect from bisect import bisect_left, bisect_right import operator from operator import itemgetter, attrgetter import itertools import collections inf = float('inf') sys.setrecursionlimit(10000) def tree(): return collections.defaultdict(tree) def cache(func): # Decorator for memoizing a function cache_dict = {} def _cached_func(*args, _get_cache=False): if _get_cache: return cache_dict if args in cache_dict: return cache_dict[args] cache_dict[args] = func(*args) return cache_dict[args] return _cached_func def equal(x, y, epsilon=1e-6): # https://code.google.com/codejam/kickstart/resources/faq#real-number-behavior if -epsilon <= x - y <= epsilon: return True if -epsilon <= x <= epsilon or -epsilon <= y <= epsilon: return False return (-epsilon <= (x - y) / x <= epsilon or -epsilon <= (x - y) / y <= epsilon) def get(_type): # For easy input if type(_type) == list: if len(_type) == 1: _type = _type[0] return list(map(_type, input().strip().split())) else: return [_type[i](inp) for i, inp in enumerate(input().strip().split())] else: return _type(input().strip()) if __name__ == '__main__': print(solve()) ```
instruction
0
67,828
24
135,656
No
output
1
67,828
24
135,657
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,531
24
137,062
Tags: dp, greedy, math Correct Solution: ``` i_speed, f_speed = input().split(" ") time, transition = input().split(" ") i_speed = int(i_speed) f_speed = int(f_speed) time = int(time) transition = int(transition) path = [ i_speed ] * time for i in range( 1, len(path) ): path[i] += transition*i while path[i] > f_speed + transition*(len(path)-i-1): path[i] -= 1 print(sum(path)) ```
output
1
68,531
24
137,063
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,532
24
137,064
Tags: dp, greedy, math Correct Solution: ``` #for _ in range(int(input())): import math v1,v2= map(int, input().split()) t,d= map(int, input().split()) ans=v1+v2 speed=v1 rem=t-2+1 for i in range(t-2): if speed+d-(rem-1)*d<=v2: speed+=d ans+=speed rem-=1 else: x=v2+(rem-1)*d-speed if x==0: ans+=speed rem-=1 elif x>0: speed+=x ans+=speed rem-=1 else: speed-=min(d,abs(v2+(rem-1)*d-speed)) ans+=speed rem-=1 print(ans) ```
output
1
68,532
24
137,065
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,533
24
137,066
Tags: dp, greedy, math Correct Solution: ``` def arr_inp(n): if n == 1: return [int(x) for x in stdin.readline().split()] elif n == 2: return [float(x) for x in stdin.readline().split()] else: return [str(x) for x in stdin.readline().split()] def dp(): p = 0 mem[p, v1] = v1 for i in range(2, t + 1): p = not p for j in range(-500, 600): # avoid last iteration mem[p, j] = float('-inf') for k in range(-d, d + 1): mem[p, j] = max(mem[p, j], j + mem[not p, j + k]) return mem[p, v2] from sys import stdin from collections import * from math import ceil v1, v2 = arr_inp(1) t, d = arr_inp(1) mem = defaultdict(lambda: float('-inf')) print(dp()) # print(mem) ```
output
1
68,533
24
137,067
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,534
24
137,068
Tags: dp, greedy, math Correct Solution: ``` import itertools v1, v2 = map(int, str.split(input())) t, d = map(int, str.split(input())) cv = v1 s = v1 + v2 steps = list(itertools.accumulate((v1,) + tuple(range(2, t)), lambda x, _: x + d)) + [v2] for i in range(t - 1, -1, -1): if steps[i - 1] - steps[i] > d: steps[i - 1] = steps[i] + d else: break print(sum(steps)) ```
output
1
68,534
24
137,069
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,535
24
137,070
Tags: dp, greedy, math Correct Solution: ``` u1, u2=map(int, input().split()) t, d=map(int,input().split()) if u1 > u2: u1,u2=u2,u1 s = [u1 for i in range(t-1)] s.append(u2) l=1 r=t-2 for i in range(t-2, 0, -1): s[i]=s[i+1]+d i =1 while s[i] -s[i-1]>d: s[i]=s[i-1]+d i+=1 print(sum(s)) ```
output
1
68,535
24
137,071
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,536
24
137,072
Tags: dp, greedy, math Correct Solution: ``` v1,v2 = map(int,input().split()) t,d = map(int,input().split()) if v1>v2: z = v1 v1 = v2 v2 = z ans = v1 cur = v1 for i in range(2,t+1): temp = (t-i)*d f = 0 for j in range(d,-1,-1): if abs((cur+j)-v2)<=temp: f=1 cur += j ans+=cur break #print(cur,ans,i) if f==0: req = cur-v2 z = i if (req%d)!=0: cur-=(req%d) z = i+1 ans+=cur for j in range(z,t+1): cur-=d if cur>=v2: ans+=cur else: ans+=v2 break #print(j) print(ans) ```
output
1
68,536
24
137,073
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,537
24
137,074
Tags: dp, greedy, math Correct Solution: ``` v1, v2 = map(int, input().split()) t, d = map(int, input().split()) a = [0]*t a[0] = v1 a[t-1] = v2 for i in range(1, t-1): a[i] = a[i-1]+d k = t-1 while abs(a[k]-a[k-1]) > d: if a[k]-a[k-1] > 0: a[k-1] = a[k]-d else: a[k-1] = a[k]+d k -= 1 print(sum(a)) ```
output
1
68,537
24
137,075
Provide tags and a correct Python 3 solution for this coding contest problem. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters.
instruction
0
68,538
24
137,076
Tags: dp, greedy, math Correct Solution: ``` u,v=(int(i) for i in input().split()) t,d=(int(i) for i in input().split()) dist=0 for i in range(t): dist+=min(u+(d*i),v+(d*(t-i-1))) print(dist) ```
output
1
68,538
24
137,077
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` import os import sys from io import BytesIO, IOBase # --------------------------------- SOLUTION --------------------------------- def main(): v1, v2 = map(int, input().split()) t, d = map(int, input().split()) if v2 < v1: v1, v2 = v2, v1 ans = v1+v2 i = 1 sec_distance = v1 + d while sec_distance < v2 + d*(t-2-i): sec_distance = v1 + d*i ans += sec_distance i += 1 for j in range(t-2, i-1, -1): ans += v2 + d*(t-1-j) print(ans) # --------------------------------- FAST IO --------------------------------- 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") # --------------------------------- MAIN --------------------------------- if __name__ == "__main__": main() ```
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` v1, v2 = [int(c) for c in input().split()] t, d = [int(c) for c in input().split()] dist = v1 # distance after the first interval [0, 1) i = 1 # interval # check the intervals [i, i+1) while(i <= t-2): dist += min(v1 + i*d, (v2 + (t-1)*d) - i*d) i += 1 dist += v2 # last interval [t-1, t) print(dist) ```
instruction
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Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` v1, v2 = map(int, input().split()) t, d = map(int, input().split()) ans = 0 l = [0] * t l[0] = v1; l[-1] = v2 i = 1; j = t-2; while 1: if i < j: l[i] = l[i-1] + d l[j] = l[j+1] + d elif i == j: l[i] = l[i-1] + d elif i > j: break i += 1 j -= 1 for i in range(1, t): if l[i] - l[i-1] > d: l[i] = l[i-1] + d for i in range(t-2, -1, -1): if l[i] - l[i+1] > d: l[i] = l[i+1] + d print(sum(l)) ```
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` __author__ = 'clumpytuna' v1, v2 = map(int, input().split(" ")) t, d = map(int, input().split(" ")) sum = v1 z = d for i in range(2, t): if ((v1+d) - (t-i)*d) <= v2: v1 += d sum += v1 #print(v1) else: while ((v1+z) - (t-i)*d) > v2: z -= 1 v1 = v1 + z sum += v1 #//print(v1, 'df') z = d print(sum+v2) ```
instruction
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` a, b = map(int, input().split(' ')) t, d = map(int, input().split(' ')) dist=0 t-=1 dist+=a if d == 0: print(a*t+t) else: while (a-b)+d<=(t-1)*d: a += d dist += a t -= 1 if t != 0: k=(a-b)%d a += k t -= 1 dist += a while t > 0: a -= d t -= 1 dist += a print(dist) ```
instruction
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No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` v1,v2=map(int,input().split()) t,d=map(int,input().split()) l=[v1] if(d!=0 and (v2 % d ==0)): for i in range((v2//d)-2): l.append(v1+d) l.append(v2+d) l.append(v2) print(sum(l)) else: if(d!=0 and (v2 % d!=0)): print(v1*t) else: if (d==0): print(v1*t) ```
instruction
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68,544
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No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` a, b = map(int, input().split(' ')) t, d = map(int, input().split(' ')) dist=0 if d == 0: print(a*t) else: while (a-b)+d<=(t-1)*d: dist += a a += d t -= 1 k=(a-b)%d a -= k t -= 1 dist += a while t > 0: a -= d t -= 1 dist += a print(dist) ```
instruction
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68,545
24
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No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per second, and in the end it is v2 meters per second. We know that this section of the route took exactly t seconds to pass. Assuming that at each of the seconds the speed is constant, and between seconds the speed can change at most by d meters per second in absolute value (i.e., the difference in the speed of any two adjacent seconds does not exceed d in absolute value), find the maximum possible length of the path section in meters. Input The first line contains two integers v1 and v2 (1 ≀ v1, v2 ≀ 100) β€” the speeds in meters per second at the beginning of the segment and at the end of the segment, respectively. The second line contains two integers t (2 ≀ t ≀ 100) β€” the time when the car moves along the segment in seconds, d (0 ≀ d ≀ 10) β€” the maximum value of the speed change between adjacent seconds. It is guaranteed that there is a way to complete the segment so that: * the speed in the first second equals v1, * the speed in the last second equals v2, * the absolute value of difference of speeds between any two adjacent seconds doesn't exceed d. Output Print the maximum possible length of the path segment in meters. Examples Input 5 6 4 2 Output 26 Input 10 10 10 0 Output 100 Note In the first sample the sequence of speeds of Polycarpus' car can look as follows: 5, 7, 8, 6. Thus, the total path is 5 + 7 + 8 + 6 = 26 meters. In the second sample, as d = 0, the car covers the whole segment at constant speed v = 10. In t = 10 seconds it covers the distance of 100 meters. Submitted Solution: ``` v1,v2 = map(int,input().split()) t,d = map(int,input().split()) if v1>v2: z = v1 v1 = v2 v2 = z ans = v1 cur = v1 for i in range(2,t+1): temp = (t-i)*d f = 0 for j in range(d,-1,-1): if abs((cur+j)-v2)<=temp: f=1 cur += j ans+=cur break if f==0: for j in range(i,t+1): cur-=d if cur>=v2: ans+=cur else: ans+=v2 break print(ans) ```
instruction
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68,546
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No
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Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
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68,649
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Tags: *special, graphs, implementation Correct Solution: ``` n = int(input()) names_set = set() s = {} names = [] arr = [[] for j in range(n)] g = 0 for i in range(n): el = input() names_set.add(el.split()[0]) ind = 0 if s.get(el) is None: s[el] = g names.append(el) g += 1 k = int(input()) for j in range(k): el2 = input() if s.get(el2) is None: s[el2] = g names.append(el2) g += 1 arr[s.get(el)].append(s.get(el2)) if i != n - 1: r = input() res = [] q = [] q.append(0) sp = {} while len(q): el = q[0] del q[0] name, vers = names[el].split() if name in names_set: try: sp[name] = max(int(vers), sp[name]) except: sp[name] = int(vers) if not len(q): for i in sp: names_set.remove(i) new_el = [] new_el.append(i) new_el.append(sp[i]) res.append(new_el[:]) ind = s[str(new_el[0]) + " " + str(new_el[1])] for j in range(len(arr[ind])): p = arr[ind][j] q.append(p) sp = {} res = res[1:] res.sort() print(len(res)) for i in res: print(i[0], i[1]) ```
output
1
68,649
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Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,650
24
137,300
Tags: *special, graphs, implementation Correct Solution: ``` from queue import Queue def main(): n = int(input()) d = {} res = {} start = None for i in range(n): project, version = input().split() version = int(version) if i == 0: start = project, version k = int(input()) if project not in d: d[project] = {} if version not in d[project]: d[project][version] = [] for j in range(k): p, v = input().split() v = int(v) d[project][version].append((p, v)) if i != n-1: input() q = Queue() q.put(start) k = 1 while not q.empty(): append = {} for i in range(k): s_p, s_v = q.get() for (p, v) in d[s_p][s_v]: if p == start[0]: continue if p in res: continue if p not in append or append[p] < v: append[p] = v k = len(append) for p in append: res[p] = append[p] q.put((p, append[p])) ans = [] for p in res: v = res[p] ans.append((p, v)) ans = sorted(ans, key= lambda z: z[0]) print(len(ans)) for (p, v) in ans: print(p, v) main() ```
output
1
68,650
24
137,301
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,651
24
137,302
Tags: *special, graphs, implementation Correct Solution: ``` # f = open("input.txt") # def readline(): # return f.readline().strip() def readline(): return input() def read_project(): project = readline().split(" ") project[1] = int(project[1]) dep_num = int(readline()) deps = {} for _ in range(0, dep_num): (proj, version) = readline().split(" ") version = int(version) if proj in deps: deps[proj] = max(deps[proj], version) else: deps[proj] = version return (tuple(project), deps) def make_like_buck(): projects_num = int(readline()) projects = {} polikarp_proj = None for ind in range(0, projects_num): (proj, deps) = read_project() if ind == 0: polikarp_proj = proj projects[proj] = deps if ind != projects_num - 1: readline() RESULT_DEPS = {polikarp_proj[0]: polikarp_proj[1]} curr_proj = [polikarp_proj] while len(curr_proj) > 0: curr_deps = {} for proj in curr_proj: new_deps = projects[proj] for proj in new_deps: if proj in RESULT_DEPS: continue if proj in curr_deps: curr_deps[proj] = max(curr_deps[proj], new_deps[proj]) else: curr_deps[proj] = new_deps[proj] RESULT_DEPS = {**RESULT_DEPS, **curr_deps} curr_proj = list(curr_deps.items()) RESULT_DEPS.pop(polikarp_proj[0]) print(len(RESULT_DEPS)) items = ["%s %s" % x for x in sorted(list(RESULT_DEPS.items()))] print("\n".join(items)) make_like_buck() ```
output
1
68,651
24
137,303
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,652
24
137,304
Tags: *special, graphs, implementation Correct Solution: ``` def read_pack(): name, ver = input().strip().split() return (name, int(ver)) n = int(input()) deps = dict() for i in range(n): pack = read_pack() if not i: root = pack dep_n = int(input()) deps[pack] = [read_pack() for _ in range(dep_n)] if i != n - 1: input() queue = [(root, 0)] taken = {root[0]: (root[1], 0)} for pack, level in queue: if pack[0] in taken and pack[1] != taken[pack[0]][0]: continue for dep in deps[pack]: if dep[0] not in taken or taken[dep[0]][1] == level + 1 and taken[dep[0]][0] < dep[1]: taken[dep[0]] = (dep[1], level + 1) queue.append((dep, level + 1)) del taken[root[0]] print(len(taken)) for d in sorted(taken): print(d, taken[d][0]) ```
output
1
68,652
24
137,305
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,653
24
137,306
Tags: *special, graphs, implementation Correct Solution: ``` def read_pack(): name, ver = input().strip().split() return (name, int(ver)) n = int(input()) deps = dict() for i in range(n): pack = read_pack() if not i: root = pack dep_n = int(input()) deps[pack] = [read_pack() for _ in range(dep_n)] if i != n - 1: input() queue = [(root, 0)] taken = {root[0]: (root[1], 0)} for pack, level in queue: # pack_deps = sorted(deps[pack], key=lambda x: x[1], reverse=True) for dep in deps[pack]: if dep[0] not in taken: taken[dep[0]] = (dep[1], level + 1) queue.append((dep, level + 1)) elif taken[dep[0]][1] == level + 1 and taken[dep[0]][0] < dep[1]: index = queue.index(((dep[0], taken[dep[0]][0]), level + 1)) taken[dep[0]] = (dep[1], level + 1) queue[index] = (dep, level + 1) del taken[root[0]] print(len(taken)) for d in sorted(taken): print(d, taken[d][0]) ```
output
1
68,653
24
137,307
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,654
24
137,308
Tags: *special, graphs, implementation Correct Solution: ``` from sys import stdin, stdout def read_pack(): name, ver = stdin.readline().split() return (name, int(ver)) n = int(input()) deps = dict() for i in range(n): pack = read_pack() if not i: root = pack dep_n = int(input()) deps[pack] = [read_pack() for _ in range(dep_n)] if i != n - 1: input() queue = [(root, 0)] taken = {root[0]: (root[1], 0)} for pack, level in queue: # pack_deps = sorted(deps[pack], key=lambda x: x[1], reverse=True) for dep in deps[pack]: if dep[0] not in taken: taken[dep[0]] = (dep[1], level + 1) queue.append((dep, level + 1)) elif taken[dep[0]][1] == level + 1 and taken[dep[0]][0] < dep[1]: index = queue.index(((dep[0], taken[dep[0]][0]), level + 1)) taken[dep[0]] = (dep[1], level + 1) queue[index] = (dep, level + 1) del taken[root[0]] print(len(taken)) for d in sorted(taken): print(d, taken[d][0]) ```
output
1
68,654
24
137,309
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,655
24
137,310
Tags: *special, graphs, implementation Correct Solution: ``` def scan_project(): name, version_str = input().split() return (name, int(version_str)) n = int(input()) projects, depends = [], {} for i in range(n): if i > 0: input() project = scan_project() projects.append(project) depends[project] = [scan_project() for j in range(int(input()))] root_name, root_version = projects[0] level_depends = [projects[0]] all_depends = {root_name : root_version} while level_depends: level_depends = list(sorted(set([(name, version) for proj in level_depends for name, version in depends[proj] if name not in all_depends]))) for name, version in sorted(level_depends): all_depends[name] = version level_depends = [(name, version) for name, version in level_depends if all_depends[name] == version] all_depends.pop(root_name) print(len(all_depends)) for name in sorted(all_depends): print(name, all_depends[name]) ```
output
1
68,655
24
137,311
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image>
instruction
0
68,656
24
137,312
Tags: *special, graphs, implementation Correct Solution: ``` def read_pack(): name, ver = input().split() return (name, int(ver)) n = int(input()) deps = dict() for i in range(n): pack = read_pack() if not i: root = pack dep_n = int(input()) deps[pack] = [read_pack() for _ in range(dep_n)] if i != n - 1: input() queue = [(root, 0)] taken = {root[0]: (root[1], 0)} for pack, level in queue: # pack_deps = sorted(deps[pack], key=lambda x: x[1], reverse=True) for dep in deps[pack]: if dep[0] not in taken: taken[dep[0]] = (dep[1], level + 1) queue.append((dep, level + 1)) elif taken[dep[0]][1] == level + 1 and taken[dep[0]][0] < dep[1]: index = queue.index(((dep[0], taken[dep[0]][0]), level + 1)) taken[dep[0]] = (dep[1], level + 1) queue[index] = (dep, level + 1) del taken[root[0]] print(len(taken)) for d in sorted(taken): print(d, taken[d][0]) ```
output
1
68,656
24
137,313
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` from collections import defaultdict def rp(): s = input().split() return (s[0], int(s[1])) ps = {} n = int(input()) for i in range(n): p = rp() d = [] for _ in range(int(input())): d += [rp()] ps[p] = d if i != n - 1: input() root = list(ps.keys())[0] q = [(root, 0)] u = {root[0]: (root[1], 0)} for i, l in q: isp = i if isp[0] in u and isp[1] != u[isp[0]][0]: continue for p in ps[i]: psp = p if psp[0] not in u or u[psp[0]][1] == l + 1 and u[psp[0]][0] < psp[1]: u[psp[0]] = (psp[1], l + 1) q.append((psp, l + 1)) del u[root[0]] print(len(u)) for i in sorted(u): print(i, u[i][0]) ```
instruction
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68,657
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Yes
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1
68,657
24
137,315
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` # python3 def read_project_name(): name, version = input().split() return (name, int(version)) def read_project(): project = read_project_name() deps_size = int(input()) deps = [read_project_name() for __ in range(deps_size)] return (project, deps) def main(): dependencies = dict() n = int(input()) - 1 main_project, deps = read_project() dependencies[main_project] = deps queue = (main_project,) for __ in range(n): input() project, deps = read_project() dependencies[project] = deps selected = dict() while queue: new_selected = dict() for (name, version) in queue: if name not in selected: old = new_selected.get(name, 0) new_selected[name] = max(old, version) queue = list() for project in new_selected.items(): queue.extend(dependencies[project]) selected.update(new_selected) del selected[main_project[0]] print(len(selected)) for (name, version) in sorted(selected.items()): print(name, version) main() ```
instruction
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68,658
24
137,316
Yes
output
1
68,658
24
137,317
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` from queue import Queue def BFS(v): global ans stack = Queue() stack.put(v) used = {p[0]: False for p in graph.keys()} used[v[0]] = True while True: set_ = dict() st = Queue() while not stack.empty(): v = stack.get() for u in graph[v]: n_ = u[0] if not used[n_]: try: set_[n_] = max(set_[n_], u[1]) except KeyError: set_[n_] = u[1] for el in set_.items(): ans.append(el) st.put(el) used[el[0]] = True if st.empty(): break while not st.empty(): stack.put(st.get()) n = int(input()) graph = dict() for i in range(n): name, ver = input().split() k = int(input()) temp = set() for j in range(k): name_, ver_ = input().split() temp.add((name_, int(ver_))) tup = (name, int(ver)) graph[tup] = temp if i == 0: PP = tup if i + 1 != n: input() ans = list() BFS(PP) print(len(ans)) print('\n'.join([' '.join(map(str, el)) for el in sorted(ans, key=lambda x: x[0])])) ```
instruction
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Yes
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1
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137,319
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` from collections import defaultdict def rp(): s = input().split() return (s[0], int(s[1])) ps = {} n = int(input()) for i in range(n): p = rp() d = [] for _ in range(int(input())): d += [rp()] ps[p] = d if i != n - 1: input() root = list(ps.keys())[0] q = [(root, 0)] u = {root[0]: (root[1], 0)} for i, l in q: isp = i if isp[0] in u and isp[1] != u[isp[0]][0]: continue for p in ps[i]: psp = p if psp[0] not in u or u[psp[0]][1] == l + 1 and u[psp[0]][0] < psp[1]: u[psp[0]] = (psp[1], l + 1) q.append((psp, l + 1)) del u[root[0]] print(len(u)) for i in sorted(u): print(i, u[i][0]) # Made By Mostafa_Khaled ```
instruction
0
68,660
24
137,320
Yes
output
1
68,660
24
137,321
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` def e(r, p): r1 = [] if len(r) > 0: for i in sorted(r, key = lambda x: (x[0], -x[1])): u = [j[0] for j in zav] if not i[0] in u: zav.append(i) ind.append(p) r1.append(i) elif ind[u.index(i[0])] > p or (ind[u.index(i[0])] == p and zav[u.index(i[0])][1] < i[1]): del zav[u.index(i[0])] del ind[u.index(i[0])] if i in [k[0] for k in r1]: del r1[u.index(i[0])] zav.append(i) r1.append(i) ind.append(p) for i in r1: e(s[i], p + 1) s = {} x, y = '', 0 n = int(input()) for i in range(n): l = input().split(' ') a, b = ' '.join(l[:-1]), int(l[-1]) if i == 0: x, y = a, b s[(a, b)] = [] for j in range(int(input())): l1 = input().split() a1, b1 = ' '.join(l1[:-1]), int(l1[-1]) s[(a, b)] = s[(a, b)] + [(a1, b1)] if i < n - 1: input() zav = [(x, y)] ind = [0] if n > 0: e(s[(x, y)], 1) if (x, y) in zav: del zav[zav.index((x, y))] print(len(zav)) if len(zav) > 0: print('\n'.join(' '.join(str(j) for j in i) for i in sorted(zav, key = lambda x: x[0]))) ```
instruction
0
68,661
24
137,322
No
output
1
68,661
24
137,323
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` q=int(input()) a=[] reg={} for i in range(1,q): k=[] d={} z,x=input().split() reg[z+' '+x]=i-1 k.append({z:int(x)}) w=int(input()) for j in range(0,w): z,x=input().split() d[z]=max(d.get(z,x),x) k.append(d) a.append(k) input() k=[] d={} z,x=input().split() reg[z+' '+x]=q-1 k.append({z:int(x)}) w=int(input()) for j in range(0,w): z,x=input().split() d[z]=max(d.get(z,x),x) k.append(d) a.append(k) #Π²Π²ΠΎΠ΄ Π·Π°ΠΊΠΎΠ½Ρ‡ΠΈΠ»ΠΈ, ΡƒΡ€Π°! # reg,a,q ΠΈΡΠΏΠΎΠ»ΡŒΠ·ΠΎΠ²Π°Π½Π½Ρ‹ ans = [] zan = [i for i in a[0][0]] def f(ad): ad1={} for i in ad: if i not in zan: ad1[i]=ad[i] kk={} for i in ad1: zan.append(i) k=i+' '+str(ad1[i]) if k in reg: ans.append(k) kl = a[reg[k]][1] for j in kl: kk[j]=max(kk.get(j,kl[j]),kl[j]) if kk=={}: return f(kk) f(a[0][1]) print(len(ans)) ans.sort() for i in ans: print(i) ```
instruction
0
68,662
24
137,324
No
output
1
68,662
24
137,325
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` count = int(input()) graph={} def get_new_elem(): name, version = input().split() node = (name, int(version)) elem = [] for i in range(int(input())): name, version = input().split() elem.append((name, int(version))) return node, elem main, melem = get_new_elem() graph={} graph[main] = melem for i in range(count-1): input() node, elem = get_new_elem() graph[node]=elem def find_all_paths(graph, start, end, path=[]): path = path + [start] if start == end: return [path] if start not in graph: return [] paths = [] for node in graph[start]: if node not in path: newpaths = find_all_paths(graph, node, end, path) for newpath in newpaths: paths.append(newpath) return paths def form_result(old_result, new_elem): name, count, version = new_elem[-1][0], len(new_elem), new_elem[-1][1] prevs = new_elem[:-1] for prev in prevs: prev_name, prev_version = prev if prev_name in old_result: _, old_version = old_result[prev_name] if old_version != prev_version: return old_result if name in old_result: old_count, old_version = old_result[name] if count < old_count: old_result[name] = (count, version) elif count == old_count: if version > old_version: old_result[name] = (count, version) else: old_result[name] = (count, version) return old_result result = {} graph_paths = [] for elem in graph: paths = find_all_paths(graph, main, elem) if len(paths) != 1: if paths: for path in paths: graph_paths.append(path) else: graph_paths.append(paths[0]) for path in sorted(graph_paths, key=len): result = form_result(result, path) del result[main[0]] print(len(result)) for res in result: print(res, result[res][1]) ```
instruction
0
68,663
24
137,326
No
output
1
68,663
24
137,327
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp is currently developing a project in Vaja language and using a popular dependency management system called Vamen. From Vamen's point of view both Vaja project and libraries are treated projects for simplicity. A project in Vaja has its own uniqie non-empty name consisting of lowercase latin letters with length not exceeding 10 and version β€” positive integer from 1 to 106. Each project (keep in mind that it is determined by both its name and version) might depend on other projects. For sure, there are no cyclic dependencies. You're given a list of project descriptions. The first of the given projects is the one being developed by Polycarp at this moment. Help Polycarp determine all projects that his project depends on (directly or via a certain chain). It's possible that Polycarp's project depends on two different versions of some project. In this case collision resolving is applied, i.e. for each such project the system chooses the version that minimizes the distance from it to Polycarp's project. If there are several options, the newer (with the maximum version) is preferred. This version is considered actual; other versions and their dependencies are ignored. More formal, choose such a set of projects of minimum possible size that the following conditions hold: * Polycarp's project is chosen; * Polycarp's project depends (directly or indirectly) on all other projects in the set; * no two projects share the name; * for each project x that some other project in the set depends on we have either x or some y with other version and shorter chain to Polycarp's project chosen. In case of ties the newer one is chosen. Output all Polycarp's project's dependencies (Polycarp's project itself should't be printed) in lexicographical order. Input The first line contains an only integer n (1 ≀ n ≀ 1 000) β€” the number of projects in Vaja. The following lines contain the project descriptions. Each project is described by a line consisting of its name and version separated by space. The next line gives the number of direct dependencies (from 0 to n - 1) and the dependencies themselves (one in a line) in arbitrary order. Each dependency is specified by its name and version. The projects are also given in arbitrary order, but the first of them is always Polycarp's. Project descriptions are separated by one empty line. Refer to samples for better understanding. It's guaranteed that there are no cyclic dependencies. Output Output all Polycarp's project's dependencies in lexicographical order. Examples Input 4 a 3 2 b 1 c 1 Β  b 2 0 Β  b 1 1 b 2 Β  c 1 1 b 2 Output 2 b 1 c 1 Input 9 codehorses 5 3 webfrmk 6 mashadb 1 mashadb 2 Β  commons 2 0 Β  mashadb 3 0 Β  webfrmk 6 2 mashadb 3 commons 2 Β  extra 4 1 extra 3 Β  extra 3 0 Β  extra 1 0 Β  mashadb 1 1 extra 3 Β  mashadb 2 1 extra 1 Output 4 commons 2 extra 1 mashadb 2 webfrmk 6 Input 3 abc 1 2 abc 3 cba 2 abc 3 0 cba 2 0 Output 1 cba 2 Note The first sample is given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«aΒ» (version 3) depends on are painted black. <image> The second sample is again given in the pic below. Arrow from A to B means that B directly depends on A. Projects that Polycarp's project Β«codehorsesΒ» (version 5) depends on are paint it black. Note that Β«extra 1Β» is chosen instead of Β«extra 3Β» since Β«mashadb 1Β» and all of its dependencies are ignored due to Β«mashadb 2Β». <image> Submitted Solution: ``` def respecc(data=None): # WE RESPECC BUT WE ALSO CALLBACC # For unittests if data is None: gen_data = input else: data_iter = iter(data.split('\n')) gen_data = data_iter.__next__ # Π’Π²ΠΎΠ΄ projects = {} n_projects = int(gen_data()) root = None for i in range(n_projects): name = gen_data() if not root: root = name num_dep = int(gen_data()) deps = [] for _ in range(num_dep): deps.append(gen_data()) projects[name] = deps if i < n_projects-1: gen_data() graph = Graph(root, projects) result = sorted(graph.final_list) x = str(len(result))+'\n'+'\n'.join(result) return x class Graph: def __init__(self, root, deps): self.root = root children = deps.pop(root) self.nodes = {root: {'children': children, 'distance': 0}} for c in deps: ch = deps.get(c, []) self.nodes[c] = {'children': ch, 'distance': 9999} self.walk(self.nodes[self.root]) r_n, r_v = split_dep(root) self.rel_list = {r_n: {'v': r_v, 'distance':0}} self.pop_rels(self.nodes[self.root]) self.final_list = set() self.final_walk(self.nodes[self.root]) def walk(self, node): for c in node['children']: child = self.nodes[c] child['distance'] = min(node['distance']+1, child['distance']) self.walk(child) def pop_rels(self, node): for c in node['children']: added = False if c not in self.nodes: continue child = self.nodes[c] name, ver = split_dep(c) if name in self.rel_list: other = self.rel_list[name] if ver == other['v']: pass elif child['distance'] < other['distance'] or (child['distance'] == other['distance'] and ver > other['v']): iconic_name = name + ' ' + str(self.rel_list[name]['v']) self.rel_list[name]['v'] = ver self.rel_list[name]['distance'] = child['distance'] self.deep_deletion(iconic_name) added = True else: if c in self.nodes: self.nodes.pop(c) else: self.rel_list[name] = {'v': ver, 'distance': child['distance']} added = True if added: self.pop_rels(child) def deep_deletion(self, node_name): node = self.nodes.get(node_name) if node: for c in node['children']: self.deep_deletion(c) n, v = split_dep(node_name) if self.rel_list.get(n, {}).get('v') == v: self.rel_list.pop(n) self.nodes.pop(node_name) def final_walk(self, node): for c in node['children']: if c in self.nodes: self.final_list.update([c]) self.final_walk(self.nodes[c]) def split_dep(dep): s = dep.split(' ') s[1] = int(s[1]) return s def dep_name(dep): return split_dep(dep)[0] def dep_v(dep): return split_dep(dep)[1] if __name__ == '__main__': print(respecc()) ```
instruction
0
68,664
24
137,328
No
output
1
68,664
24
137,329
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,856
24
139,712
Tags: implementation Correct Solution: ``` #Codeforce 1095A s=int(input()) str1=input() str2="" k=int((s*2)**0.5) for i in range(k): str2 += str1[i*(i+1)//2] print(str2) ```
output
1
69,856
24
139,713
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,857
24
139,714
Tags: implementation Correct Solution: ``` n=int(input()) s=input() a='' c=1 i=1 while c <= len(s): a+=s[c-1] i+=1 c=(i*(i+1))//2 print(a) ```
output
1
69,857
24
139,715
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,858
24
139,716
Tags: implementation Correct Solution: ``` n = input();a =0 if len(n)%2==0:x = n[-1];n = n[0:len(n)-1];a=1 z = len(n)//2 s = n[z] for i in range(1,z+1): s+=n[z+i] s+=n[z-i] if a ==1:print(s+x) else:print(s) ```
output
1
69,858
24
139,717
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,859
24
139,718
Tags: implementation Correct Solution: ``` n = int(input()) s = input() i = 0 count = 0 while i<n : print(s[i], end = '') count+=1 i+=count ```
output
1
69,859
24
139,719
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,860
24
139,720
Tags: implementation Correct Solution: ``` n=int(input()) s=input() a=1 i=0 while i!=n: print(s[i],end='') i+=a a+=1 ```
output
1
69,860
24
139,721
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,861
24
139,722
Tags: implementation Correct Solution: ``` n=int(input()) s=input() x=((1+8*n)**0.5-1)/2 #print(int(x)) p='' k=0 for i in range(1,int(x)+1): p=p+s[k] k=k+i print(p) ```
output
1
69,861
24
139,723
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,862
24
139,724
Tags: implementation Correct Solution: ``` import sys import math n=int(input()) s=sys.stdin.readline().strip() res=[] count=1 L=(math.sqrt(1+8*n)-1)//2 i=0 while count<=L: res.append(s[i]) i+=count count+=1 es="".join(res) print(es) ```
output
1
69,862
24
139,725
Provide tags and a correct Python 3 solution for this coding contest problem. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z
instruction
0
69,863
24
139,726
Tags: implementation Correct Solution: ``` t = int(input()) s = input() i = 0; j = 1; while i < t: print(s[i], end = '') i += j j += 1 ```
output
1
69,863
24
139,727
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z Submitted Solution: ``` in1 = int(input()) in2 = input() i = 0 j = 1 s = '' while i < in1: s = s + in2[i] j = j + 1 i = i + j print(s) ```
instruction
0
69,864
24
139,728
Yes
output
1
69,864
24
139,729
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z Submitted Solution: ``` def A(): n = int(input()) s = input() triang = lambda x: int(x*(x+1)/2) r = "" i = 0 while(triang(i)<n): r+=s[triang(i)] i+=1 print(r) A() ```
instruction
0
69,865
24
139,730
Yes
output
1
69,865
24
139,731
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z Submitted Solution: ``` a=int(input()) s=input() i=0 k='' b=1 while(i<a): k+=s[i] i=i+b b=b+1 print(k) ```
instruction
0
69,866
24
139,732
Yes
output
1
69,866
24
139,733
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z Submitted Solution: ``` n = int(input()) a = input() i = 1 s = 1 new = [] while s <= n: new.append(a[s-1]) i += 1 s += i str = ''.join(new) print(str) ```
instruction
0
69,867
24
139,734
Yes
output
1
69,867
24
139,735
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z Submitted Solution: ``` ''' Amirhossein Alimirzaei Telegram : @HajLorenzo Instagram : amirhossein_alimirzaei University of Bojnourd ''' n=input() tmp="" ln=len(n) i=(ln//2)-1 switcher=True while(len(tmp)!=ln): tmp+=n[i] if(switcher): i+=len(tmp) switcher=False else: i-=len(tmp) switcher=True #print("tmp : ",tmp) print(tmp) ```
instruction
0
69,868
24
139,736
No
output
1
69,868
24
139,737
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Polycarp loves ciphers. He has invented his own cipher called repeating. Repeating cipher is used for strings. To encrypt the string s=s_{1}s_{2} ... s_{m} (1 ≀ m ≀ 10), Polycarp uses the following algorithm: * he writes down s_1 ones, * he writes down s_2 twice, * he writes down s_3 three times, * ... * he writes down s_m m times. For example, if s="bab" the process is: "b" β†’ "baa" β†’ "baabbb". So the encrypted s="bab" is "baabbb". Given string t β€” the result of encryption of some string s. Your task is to decrypt it, i. e. find the string s. Input The first line contains integer n (1 ≀ n ≀ 55) β€” the length of the encrypted string. The second line of the input contains t β€” the result of encryption of some string s. It contains only lowercase Latin letters. The length of t is exactly n. It is guaranteed that the answer to the test exists. Output Print such string s that after encryption it equals t. Examples Input 6 baabbb Output bab Input 10 ooopppssss Output oops Input 1 z Output z Submitted Solution: ``` n = int(input()) s = input() k = 0 if n==1: print(s[0]) elif n > 1: print(s[0],end='') for i in range(n): k+=i if k < n: print(s[k]) ```
instruction
0
69,869
24
139,738
No
output
1
69,869
24
139,739