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Provide tags and a correct Python 3 solution for this coding contest problem. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite.
instruction
0
94,841
15
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Tags: implementation Correct Solution: ``` n = int(input()) s = input() p = 0 k = 0 a = list(map(int, input().split())) for i in range(2 * n): if s[p] == '>': p += a[p] else: p -= a[p] if (p > n - 1) or (p < 0): print("FINITE") k = 1 break if not k: print("INFINITE") ```
output
1
94,841
15
189,683
Provide tags and a correct Python 3 solution for this coding contest problem. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite.
instruction
0
94,842
15
189,684
Tags: implementation Correct Solution: ``` def main(): n = int(input()) arrows = input() cells = [int(x) for x in input().split()] print(solver(arrows, cells)) def solver(arrows, cells): for i in range(len(arrows)): if arrows[i] == '<': cells[i] = - cells[i] visited = [False] * len(cells) index = 0 while True: if index >= len(cells) or index < 0: return "FINITE" elif visited[index] == True: return "INFINITE" else: visited[index] = True index = index + cells[index] #print(solver(">><", [2, 1, 1])) #print(solver("><", [1, 2])) main() ```
output
1
94,842
15
189,685
Provide tags and a correct Python 3 solution for this coding contest problem. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite.
instruction
0
94,843
15
189,686
Tags: implementation Correct Solution: ``` n = int(input())-1 s = input() d = [int(i) for i in input().split()] c = True cnt = 0 i = 0 z = 0 while i<=n and i>=0: if s[i]: if s[i]==">": i+=d[i] z+=1 elif s[i]=="<": i-=d[i] z+=1 else: break if z>=2*n:c=False;break if i>n or i<0: print("FINITE") else: print("INFINITE") ```
output
1
94,843
15
189,687
Provide tags and a correct Python 3 solution for this coding contest problem. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite.
instruction
0
94,844
15
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Tags: implementation Correct Solution: ``` if __name__ == '__main__': Y = lambda: list(map(int, input().split())) N = lambda: int(input()) n = N() s = input() a = Y() nxt, ans = 0, 0 for i in range(n): nxt += [a[nxt], -a[nxt]][s[nxt] == '<'] if nxt >= n or nxt < 0: ans = 2 break print("INFINITE"[ans:]) ```
output
1
94,844
15
189,689
Provide tags and a correct Python 3 solution for this coding contest problem. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite.
instruction
0
94,845
15
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Tags: implementation Correct Solution: ``` n=int(input()) s=input() a=list(map(int,input().split())) f=n*[False] i,j=0,0 while True: # print(i,f[i]) if i<0 or i>=n or n==1: print("FINITE") break elif f[i]==True: print("INFINITE") break else: f[i]=True if s[i]=='>': i+=a[i] else: i-=a[i] ```
output
1
94,845
15
189,691
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` import math def main_function(): n = int(input()) s = input() a = [int(i) for i in input().split(" ")] current_position = 0 hash = [0 for i in range(100000)] while True: if current_position < 0 or current_position > n - 1: print("FINITE") break else: if hash[current_position] == 1: print("INFINITE") break else: hash[current_position] = 1 if s[current_position] == ">": current_position += a[current_position] else: current_position -= a[current_position] main_function() ```
instruction
0
94,846
15
189,692
Yes
output
1
94,846
15
189,693
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` n = int(input()) D = [d if ch=='>' else -d for ch,d in zip(input(), map(int, input().split()))] i = 0 visited = {0} while True: i += D[i] if i < 0 or i >= n: print('FINITE') break if i in visited: print('INFINITE') break visited.add(i) ```
instruction
0
94,847
15
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Yes
output
1
94,847
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` def main(): n = int(input()) d = input() l = [int(c) for c in input().split()] visited = {0} i = 0 while 0 <= i < n: di, li = d[i], l[i] i = i + li if di == '>' else i - li if i in visited: print('INFINITE') return visited.add(i) print('FINITE') if __name__ == '__main__': main() ```
instruction
0
94,848
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Yes
output
1
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` n = int(input()) s = input() a = list(map(int, input().split())) WAS = False pos = 1 for i in range(0, n) : if s[pos - 1] == '<' : pos -= a[pos - 1] else : pos += a[pos - 1] if pos < 1 or pos > n : WAS = True if WAS : break if WAS : print("FINITE") else : print("INFINITE") ```
instruction
0
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Yes
output
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` n=int(input()) S=input() l=list(map(int,input().split())) i=0 c=1 while i>=0 or i>=n-1 : if S[i]=='>' and i+l[i]>n-1 : c=1 break if S[i]=='<' and i-l[i]<0 : c=1 break if l[i]==0 : c=0 break if S[i]=='>' : i=i+l[i] else : i=i-l[i] l[i]=0 if c==1 : print('FINITE') else : print('INFINITE') ```
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. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` n=int(input()) s=input() l=list(map(int,input().split())) c=0 for i in range(len(s)): if s[i]=='>': c+=l[i] if c>n: print('FINITE') exit() else: c-=l[i] if c<0: print('FINITE') exit() print('INFINITE') ```
instruction
0
94,851
15
189,702
No
output
1
94,851
15
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` n=int(input()) s=input() l=list(map(int,input().split())) c=0 for i in range(len(s)): if s[i]=='>': c+=l[i] else: c-=l[i] if c>n or c<0: break print(['FINITE','INFINITE'][n>c>=0]) ```
instruction
0
94,852
15
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No
output
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1 × n. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen. Input The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — length of the strip. Next line contains a string of length n which consists of characters "<" and ">" only, that provide the direction of the jump from the corresponding cell. Next line contains n integers di (1 ≤ di ≤ 109) — the length of the jump from the i-th cell. Output Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes). Examples Input 2 &gt;&lt; 1 2 Output FINITE Input 3 &gt;&gt;&lt; 2 1 1 Output INFINITE Note In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite. Submitted Solution: ``` n = int(input()) t = input() cord = 0 l = list(map(int,input().split())) i = 0 d = set({}) while cord < len(t): d.add(cord) if t[cord] == ">": cord = cord + l[i] else: cord = cord - l[i] if cord < 0 or cord > n-1: print("FINITE") exit() if cord in d: print("INFINITE") exit() ```
instruction
0
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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. Little Artem is fond of dancing. Most of all dances Artem likes rueda — Cuban dance that is danced by pairs of boys and girls forming a circle and dancing together. More detailed, there are n pairs of boys and girls standing in a circle. Initially, boy number 1 dances with a girl number 1, boy number 2 dances with a girl number 2 and so on. Girls are numbered in the clockwise order. During the dance different moves are announced and all pairs perform this moves. While performing moves boys move along the circle, while girls always stay at their initial position. For the purpose of this problem we consider two different types of moves: 1. Value x and some direction are announced, and all boys move x positions in the corresponding direction. 2. Boys dancing with even-indexed girls swap positions with boys who are dancing with odd-indexed girls. That is the one who was dancing with the girl 1 swaps with the one who was dancing with the girl number 2, while the one who was dancing with girl number 3 swaps with the one who was dancing with the girl number 4 and so one. It's guaranteed that n is even. Your task is to determine the final position of each boy. Input The first line of the input contains two integers n and q (2 ≤ n ≤ 1 000 000, 1 ≤ q ≤ 2 000 000) — the number of couples in the rueda and the number of commands to perform, respectively. It's guaranteed that n is even. Next q lines contain the descriptions of the commands. Each command has type as the integer 1 or 2 first. Command of the first type is given as x ( - n ≤ x ≤ n), where 0 ≤ x ≤ n means all boys moves x girls in clockwise direction, while - x means all boys move x positions in counter-clockwise direction. There is no other input for commands of the second type. Output Output n integers, the i-th of them should be equal to the index of boy the i-th girl is dancing with after performing all q moves. Examples Input 6 3 1 2 2 1 2 Output 4 3 6 5 2 1 Input 2 3 1 1 2 1 -2 Output 1 2 Input 4 2 2 1 3 Output 1 4 3 2 Submitted Solution: ``` # You lost the game. n,q = map(int, input().split()) Q = [list(map(int, input().split())) for _ in range(q)] impair = 0 pair = 0 pos = 1 for i in range(q): if Q[i][0] == 1: d = Q[i][1] impair += d pair += d if pos == 1 and d % 2: pos = -1 elif pos == -1 and d % 2 == 0: pos = 1 else: impair += pos pair += -pos pos = -pos for i in range(1,n+1): j = i-1 if pair % 2: if i % 2: print(1+(j-pair) % n,end=" ") else: print(1+(j-impair) % n,end=" ") else: if i % 2: print(1+(j-impair) % n,end=" ") else: print(1+(j-pair) % n,end=" ") ```
instruction
0
94,855
15
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No
output
1
94,855
15
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Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
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95,031
15
190,062
"Correct Solution: ``` import collections H,W,K = map(int,input().split()) s1,e1,s2,e2 = map(int,input().split()) s1-=1 e1-=1 s2-=1 e2-=1 L = [] board = [] for _ in range(H): a = input() L.append(a) for i in range(H): l = L[i] tmp = [] for j in range(len(l)): tmp.append(l[j]) board.append(tmp) queue = collections.deque() queue.append([0,s1,e1]) seen = [[float('inf')]*(W) for _ in range(H)] destination = [(1,0),(-1,0),(0,1),(0,-1)] while queue: cost,x,y = queue.popleft() seen[x][y] = cost if x==s2 and y ==e2: print(cost);exit() break for dx,dy in destination: X,Y = x,y for i in range(1,K+1): NX = X +i*dx NY = Y + i*dy if 0>NX or NX>=H or 0>NY or NY>=W or seen[NX][NY] < seen[X][Y]+1: break else: if board[NX][NY]=='@': break elif seen[NX][NY] ==float('inf'): queue.append([cost+1,NX,NY]) seen[NX][NY] = cost+1 print(-1) ```
output
1
95,031
15
190,063
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,032
15
190,064
"Correct Solution: ``` #!usr/bin/env python3 from collections import defaultdict, deque from heapq import heappush, heappop import sys import math def LI(): return [int(x) for x in sys.stdin.readline().split()] dd = [(1,0),(-1,0),(0,1),(0,-1)] def solve(): h,w,k = LI() y,x,s,t = LI() y -= 1 x -= 1 s -= 1 t -= 1 c = [input() for i in range(h)] q = deque([(y,x)]) d = [[float("inf")]*w for i in range(h)] d[y][x] = 0 while q: y,x = q.popleft() if (y,x) == (s,t): print(d[s][t]) return nd = d[y][x] + 1 for dy,dx in dd: ny,nx = y,x for _ in range(k): ny += dy nx += dx if 0 <= ny < h and 0 <= nx < w and c[ny][nx] != "@" and nd <= d[ny][nx]: if nd < d[ny][nx]: d[ny][nx] = nd q.append((ny,nx)) continue break print(-1) return #Solve if __name__ == "__main__": solve() ```
output
1
95,032
15
190,065
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,033
15
190,066
"Correct Solution: ``` # -*- coding: utf-8 -*- H,W,K = map(int, input().split()) x1,y1,x2,y2 = map(int, input().split()) C = [input() for _ in range(H)] T = [[-1 for _ in range(W)] for _ in range(H)] T[x1-1][y1-1] = 0 que = {(x1-1,y1-1):0} step = 1 while len(que)>0: que_next = {} for q in que.keys(): x,y = q[0],q[1] for i in range(1,K+1): if x-i<0: break if C[x-i][y]=='@' or T[x-i][y]==1: break if x-i==x2-1 and y==y2-1: print(step) exit() que_next[(x-i,y)] = 0 for i in range(1,K+1): if x+i>H-1: break if C[x+i][y]=='@' or T[x+i][y]==1: break if x+i==x2-1 and y==y2-1: print(step) exit() que_next[(x+i,y)] = 0 for i in range(1,K+1): if y-i<0: break if C[x][y-i]=='@' or T[x][y-i]==1: break if x==x2-1 and y-i==y2-1: print(step) exit() que_next[(x,y-i)] = 0 for i in range(1,K+1): if y+i>W-1: break if C[x][y+i]=='@' or T[x][y+i]==1: break if x==x2-1 and y+i==y2-1: print(step) exit() que_next[(x,y+i)] = 0 que = que_next for q in que.keys(): T[q[0]][q[1]] = 1 step += 1 print(-1) ```
output
1
95,033
15
190,067
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,034
15
190,068
"Correct Solution: ``` # import sys from collections import deque input=sys.stdin.readline def main(): H,W,K=map(int,input().split()) x1,y1,x2,y2=map(int,input().split()) x1-=1 y1-=1 x2-=1 y2-=1 mas=[list(input()) for i in range(H)] dist=[[-1]*W for i in range(H)] dist[x1][y1]=0 qu=deque([(x1,y1)]) qup=qu.popleft qua=qu.append d=((-1,0),(1,0),(0,-1),(0,1)) while(len(qu)>0): v=qup() for di in d: for i in range(1,K+1): nvh=v[0]+i*di[0] nvw=v[1]+i*di[1] if nvh<0 or nvh>=H or nvw<0 or nvw>=W or mas[nvh][nvw]=="@": break if dist[nvh][nvw]!=-1 and dist[nvh][nvw]<=dist[v[0]][v[1]]: break if dist[nvh][nvw]==-1: dist[nvh][nvw]=dist[v[0]][v[1]]+1 qua((nvh,nvw)) print(dist[x2][y2]) if __name__=="__main__": main() ```
output
1
95,034
15
190,069
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,035
15
190,070
"Correct Solution: ``` #16:41 h,w,k = map(int,input().split()) x1,y1,x2,y2 = map(lambda x:int(x)-1, input().split()) raw = [] for _ in range(h): raw.append(input()) inf = 10**6 seen = [[inf for _ in range(w)] for _ in range(h)] seen[x1][y1] = 0 from heapq import heappush as push from heapq import heappop as pop now = [[0,x1,y1]] while now: s,x,y = pop(now) if x == x2 and y == y2: print(s) exit() for i in range(1,k+1): if x-i == -1 or raw[x-i][y] == '@' or seen[x-i][y] < s+1: break if seen[x-i][y] != s+1: seen[x-i][y] = s+1 push(now,[s+1,x-i,y]) for i in range(1,k+1): if y-i == -1 or raw[x][y-i] == '@' or seen[x][y-i] < s+1: break if seen[x][y-i] != s+1: seen[x][y-i] = s+1 push(now,[s+1,x,y-i]) for i in range(1,k+1): if x+i == h or raw[x+i][y] == '@' or seen[x+i][y] < s+1: break if seen[x+i][y] != s+1: seen[x+i][y] = s+1 push(now,[s+1,x+i,y]) for i in range(1,k+1): if y+i == w or raw[x][y+i] == '@' or seen[x][y+i] < s+1: break if seen[x][y+i] != s+1: seen[x][y+i] = s+1 push(now,[s+1,x,y+i]) print(-1) ```
output
1
95,035
15
190,071
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,036
15
190,072
"Correct Solution: ``` from heapq import heappop, heappush from collections import deque def dijkstra(xs, ys, xg, yg,h,w,k,field): # que->(cost, x, y, direction) inf = 1e18 dist = [[inf]*w for _ in range(h)] dist[xs][ys] = 0 que = deque([(0, xs, ys)]) dx = [-1, 0, 1, 0] dy = [0, 1, 0, -1] while que: cost, x, y = que.popleft() if cost > dist[x][y]: continue for v in range(4): nx, ny = x, y for _ in range(k): nx += dx[v] ny += dy[v] if not field[nx][ny]: break if dist[nx][ny]<=dist[x][y]: break if dist[nx][ny] > dist[x][y]+1: dist[nx][ny] = dist[x][y]+1 que.append((dist[nx][ny], nx, ny)) if dist[xg][yg] == inf: print(-1) else: print(dist[xg][yg]) def main(): import sys def input(): return sys.stdin.readline().rstrip() h, w, k = map(int, input().split()) xs, ys, xg, yg = map(int, input().split()) field = [[False]*(w+2) for _ in range(h+2)] for i in range(h): # False で覆うことでx,yの制限をなくす。 s = [True if _ == '.' else False for _ in input()] field[i+1] = [False]+s+[False] h += 2 w += 2 dijkstra(xs, ys, xg, yg, h, w, k, field) if __name__ == '__main__': main() ```
output
1
95,036
15
190,073
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,037
15
190,074
"Correct Solution: ``` from collections import deque H,W,K = map(int,input().split()) x1,y1,x2,y2 = map(int,input().split()) maze = [] maze.append(["@"]*(W+2)) for _ in range(H): row = list(input()) maze.append(["@"]+row+["@"]) maze.append(["@"]*(W+2)) q = deque([(x1,y1)]) depth = 0 while q: for i,j in q: maze[i][j] = "@" new_q = set() l = len(q) for _ in range(l): x,y = q.pop() if (x,y) == (x2,y2): print(depth) exit() # Up for i in range(1, K+1): if maze[x-i][y] == "@": break new_q.add((x-i, y)) # Down for i in range(1, K+1): if maze[x+i][y] == "@": break new_q.add((x+i, y)) # Left for i in range(1, K+1): if maze[x][y-i] == "@": break new_q.add((x, y-i)) # Right for i in range(1, K+1): if maze[x][y+i] == "@": break new_q.add((x, y+i)) q = deque(list(new_q)) depth += 1 print(-1) ```
output
1
95,037
15
190,075
Provide a correct Python 3 solution for this coding contest problem. Snuke, a water strider, lives in a rectangular pond that can be seen as a grid with H east-west rows and W north-south columns. Let (i,j) be the square at the i-th row from the north and j-th column from the west. Some of the squares have a lotus leaf on it and cannot be entered. The square (i,j) has a lotus leaf on it if c_{ij} is `@`, and it does not if c_{ij} is `.`. In one stroke, Snuke can move between 1 and K squares (inclusive) toward one of the four directions: north, east, south, and west. The move may not pass through a square with a lotus leaf. Moving to such a square or out of the pond is also forbidden. Find the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2). If the travel from (x_1,y_1) to (x_2,y_2) is impossible, point out that fact. Constraints * 1 \leq H,W,K \leq 10^6 * H \times W \leq 10^6 * 1 \leq x_1,x_2 \leq H * 1 \leq y_1,y_2 \leq W * x_1 \neq x_2 or y_1 \neq y_2. * c_{i,j} is `.` or `@`. * c_{x_1,y_1} = `.` * c_{x_2,y_2} = `.` * All numbers in input are integers. Input Input is given from Standard Input in the following format: H W K x_1 y_1 x_2 y_2 c_{1,1}c_{1,2} .. c_{1,W} c_{2,1}c_{2,2} .. c_{2,W} : c_{H,1}c_{H,2} .. c_{H,W} Output Print the minimum number of strokes Snuke takes to travel from the square (x_1,y_1) to (x_2,y_2), or print `-1` if the travel is impossible. Examples Input 3 5 2 3 2 3 4 ..... .@..@ ..@.. Output 5 Input 1 6 4 1 1 1 6 ...... Output 2 Input 3 3 1 2 1 2 3 .@. .@. .@. Output -1
instruction
0
95,038
15
190,076
"Correct Solution: ``` #import heapq from collections import deque h,w,k = list(map(int, input().split())) x1,y1,x2,y2 = list(map(int, input().split())) x1,y1,x2,y2 = x1-1,y1-1,x2-1,y2-1 dp = [[-1]*w for _ in range(h)] #que = [] que = deque() c = [input() for _ in range(h)] dp[x1][y1] = 0 #heapq.heappush(que, (dp[x1][y1], [x1,y1])) que.append((x1,y1)) dx = [1,0,-1,0] dy = [0,1,0,-1] while que: x,y=que.popleft() if x==x2 and y==y2: exit(print(dp[x][y])) for dx,dy in [[1,0],[-1,0],[0,-1],[0,1]]: for i in range(1,k+1): xx=x+dx*i yy=y+dy*i if not(0<=xx<h and 0<=yy<w) or c[xx][yy]=="@":break if 0<=dp[xx][yy]<=dp[x][y]:break if dp[xx][yy]==-1:que.append((xx,yy)) dp[xx][yy]=dp[x][y]+1 print(-1) ```
output
1
95,038
15
190,077
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,335
15
190,670
Tags: constructive algorithms Correct Solution: ``` #------------------------------warmup---------------------------- import os import sys from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") #-------------------game starts now---------------------------------------------------- n,m=map(int,input().split()) s=0 e=n-1 for i in range(n//2): for j in range(m): print(s+1,j+1) print(e+1,m-j) s+=1 e-=1 if n%2==1: s=n//2 for j in range(m//2): print(s+1,j+1) print(s+1,m-j) if m%2==1: print(s+1,m//2+1) ```
output
1
95,335
15
190,671
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,336
15
190,672
Tags: constructive algorithms Correct Solution: ``` import sys ii = lambda: int(input()) mi = lambda: map(int, input().split()) li = lambda: list(mi()) n, m = list(map(int, sys.stdin.readline().strip().split())) upr = 1 dwr = n while(upr < dwr): upc = 1 dwc = m for i in range(m): sys.stdout.write(str(upr) + ' ' + str(upc) + '\n') sys.stdout.write(str(dwr) + ' ' + str(dwc) + '\n') upc += 1 dwc -= 1 upr += 1 dwr -= 1 if(upr == dwr): row = upr col = 1 rcol = m for i in range(m): sys.stdout.write(str(row) + ' ' + str(col) + '\n') tcol = col col = rcol rcol = (tcol + 1 if (tcol < rcol) else tcol - 1) ```
output
1
95,336
15
190,673
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,337
15
190,674
Tags: constructive algorithms Correct Solution: ``` import sys import math from collections import defaultdict n,m=map(int,sys.stdin.readline().split()) #cur=[1,1] #ans=[-1 for _ in range(2*n*m)] up,down=1,n count=0 while up<=down: left,right=1,m #ans.append(cur) while left<=m and count<n*m: #ans.append([up,left]) #ans[count]=[up,left] if count<n*m: sys.stdout.write((str(up)+" "+str(left)+"\n")) count+=1 left+=1 #ans[count]=[down,right] if count<n*m: sys.stdout.write((str(down)+" "+str(right)+"\n")) count+=1 #ans.append([down,right]) right-=1 up+=1 down-=1 '''if n==1: a=len(ans) #print(a,'a') for i in range(a//2): print(ans[i][0],ans[i][1]) else: a=len(ans) for i in range(a//2): print(ans[i][0],ans[i][1]) #print(ans)''' ```
output
1
95,337
15
190,675
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,338
15
190,676
Tags: constructive algorithms Correct Solution: ``` import sys m, n = [int(i) for i in input().split()] data = [0] * (m+1) for i in range((m+1)//2 ): data[2*i] = i+1 data[2*i+1] = m - i for x in range(n//2): for i in range(m): sys.stdout.write(str(i+1) + ' ' + str(x+1) + '\n') sys.stdout.write(str(m-i) + ' ' + str(n-x) + '\n') #print(i+1, x+1) #print(m - i, n - x) if n % 2 == 1: q = (n+1)//2 s = " " + str(q) + '\n' for i in range(m): #print(data[i], q) sys.stdout.write(str(data[i]) + s) ```
output
1
95,338
15
190,677
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,339
15
190,678
Tags: constructive algorithms Correct Solution: ``` import math import sys n,m=[int(x) for x in input().split()] answer=[] x=math.ceil(n/2) y=n%2 for i in range(1,math.ceil(n/2)+1): if y==1 and i==x: for j in range(1,m//2+1): answer.append(str(i)+' '+str(j)) answer.append(str(n-i+1)+' '+str(m-j+1)) answer.append((str(i)+' '+str((math.ceil(m/2))))) else: for j in range(1,m+1): answer.append((str(i)+' '+str(j))) answer.append(str(n-i+1)+' '+str(m-j+1)) print("\n".join(answer[:n*m])) ```
output
1
95,339
15
190,679
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,340
15
190,680
Tags: constructive algorithms Correct Solution: ``` if __name__ == "__main__": n, m = [int(x) for x in input().split()] #n, m = map(int, input().split()) answer = [] for i in range((n + 1) // 2): for j in range(m): if i == n // 2 and j == m // 2: if m % 2 == 0: break answer.append("{} {}".format(i + 1, j + 1)) break answer.append("{} {}".format(i + 1, j + 1)) answer.append("{} {}".format(n - i, m - j)) print("\n".join(answer)) ```
output
1
95,340
15
190,681
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,341
15
190,682
Tags: constructive algorithms Correct Solution: ``` n, m = tuple(map(int, input().split())) if n==1 and m==1: print('1 1') exit() def onerow(r, m): for i in range(1, (m+1)//2 + 1): # print('Here', i) print(str(r) + ' ' + str(i)) if m%2 == 0 or i != (m+1)//2: print(str(r) + ' ' + str(m+1-i)) def tworow(r1, r2, m): for i in range(1, m+1): print(str(r1) + ' ' + str(i)) print(str(r2) + ' ' + str(m+1-i)) if n%2 == 0: for i in range(1, n//2 + 1): tworow(i, n+1-i, m) if n%2 == 1: for i in range(1, n//2 + 1): tworow(i, n+1-i, m) onerow(n//2 + 1, m) ```
output
1
95,341
15
190,683
Provide tags and a correct Python 3 solution for this coding contest problem. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2).
instruction
0
95,342
15
190,684
Tags: constructive algorithms Correct Solution: ``` import sys input=sys.stdin.buffer.readline n,m=map(int,input().split()) for i in range(n//2+n%2): x1=i+1 x2=n-i if(x1==x2): for j in range(m//2+m%2): if(j+1==m-j): sys.stdout.write((str(x1)+" "+str(j+1)+"\n")) else: sys.stdout.write((str(x1)+" "+str(j+1)+"\n")) sys.stdout.write((str(x2)+" "+str(m-j)+"\n")) else: if(i%2==0): for j in range(m): sys.stdout.write((str(x1)+" "+str(j+1)+"\n")) sys.stdout.write((str(x2)+" "+str(m-j)+"\n")) else: for j in range(m): sys.stdout.write((str(x1)+" "+str(m-j)+"\n")) sys.stdout.write((str(x2)+" "+str(j+1)+"\n")) ```
output
1
95,342
15
190,685
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` import sys input = sys.stdin.readline n,m=map(int,input().split()) ANS=[] for i in range(1,n//2+1): for j in range(1,m+1): sys.stdout.write("".join((str(i)," ",str(j),"\n"))) sys.stdout.write("".join((str(n-i+1)," ",str(m-j+1),"\n"))) if n%2==1: for j in range(1,m//2+1): sys.stdout.write("".join((str(n//2+1)," ",str(j),"\n"))) sys.stdout.write("".join((str(n//2+1)," ",str(m-j+1),"\n"))) if m%2==1: sys.stdout.write("".join((str(n//2+1)," ",str(m//2+1),"\n"))) ```
instruction
0
95,343
15
190,686
Yes
output
1
95,343
15
190,687
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` n,m=map(int,input().split()) x1,y1,x2,y2=1,1,n,m for i in range(n*m): if(i&1): print(str(x2)+" "+str(y2)) if x2==1: x2,y2=n,y2-1 else: x2-=1 else: print(str(x1)+" "+str(y1)) if x1==n: x1,y1=1,y1+1 else: x1+=1 ```
instruction
0
95,344
15
190,688
Yes
output
1
95,344
15
190,689
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` n, m = list(map(int,input().split())) for i in range (0, n * m): if i % 2 == 0: c = i // (2 * n) r = (i % (2 * n)) // 2 else: c = m - 1 - i // (2 * n) r = n - 1 - (i % (2 * n)) // 2 print(str(r+1) + " " + str(c + 1)) ```
instruction
0
95,345
15
190,690
Yes
output
1
95,345
15
190,691
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` n, m = list(map(int,input().split())) ans = [] for i in range(n // 2): for j in range(m): ans.append(str(i + 1) + ' ' + str(j + 1)) ans.append(str(n - i) + ' ' + str(m - j)) if n % 2 == 1: i = n // 2 + 1 for j in range(m // 2): ans.append(str(i) + ' ' + str(j + 1)) ans.append(str(i) + ' ' + str(m - j)) if m % 2 == 1: ans.append(str(i) + ' ' + str(m // 2 + 1)) print ('\n'.join(ans)) ```
instruction
0
95,346
15
190,692
Yes
output
1
95,346
15
190,693
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` """ 111 111 11111 11111 11 15 12 14 13 23 24 22 25 21 111111 111111 11 16 12 15 13 14 24 11 11 11 11 11 11 51 21 41 31 32 42 22 52 12 1 1 1 1 1 11 51 21 41 31 """ n,m=list(map(int,input().split())) if n>2 and m>2: print(-1) exit(0) if n==1 and m==1: print(1,1) elif n==1: count=0 l=1 r=m fl=0 while count<m: if fl==0: print(1,l) l+=1 fl=1 else: print(1,r) r-=1 fl=0 count+=1 #print(l,r,end="1233") elif n==2: res=[] count=0 l=1 r=m fl=0 y=0 temp=1 while count<m: if fl==0: print(1,l) res.append(l) y=l l+=1 fl=1 else: print(1,r) res.append(r) y=r r-=1 fl=0 count+=1 while res!=[]: print(2,res[-1]) res.pop() elif m==1: #print("hhh") count=0 l=1 r=n fl=0 while count<n: if fl==0: print(l,1) l+=1 fl=1 else: print(r,1) r-=1 fl=0 count+=1 elif m==2: res=[] count=0 l=1 r=n fl=0 while count<n: if fl==0: print(l,1) res.append(l) l+=1 fl=1 else: print(r,1) res.append(r) r-=1 fl=0 count+=1 while res!=[]: print(res[-1],2) res.pop() else: print(-1) ```
instruction
0
95,347
15
190,694
No
output
1
95,347
15
190,695
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` list=[int(x) for x in input().split()] n=list[0] m=list[1] dif=n*m-1 for i in range(0,dif,2): print(i//m+1,i%m+1) print((dif-i)//m+1,(dif-i)%m+1) if dif %2==0: print(m/2+1,n/2+1) ```
instruction
0
95,348
15
190,696
No
output
1
95,348
15
190,697
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` n, m = [int(x) for x in input().split()] l = 1 r = n while l <= r: t = 1 b = m if l == r: while t <= b: print(l, t) if t != b: print(r, b) t += 1 b -= 1 else: while t <= m and b >= 0: print(l, t) if t != b: print(r, b) t += 1 b -= 1 l += 1 r -= 1 ```
instruction
0
95,349
15
190,698
No
output
1
95,349
15
190,699
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. This morning Tolik has understood that while he was sleeping he had invented an incredible problem which will be a perfect fit for Codeforces! But, as a "Discuss tasks" project hasn't been born yet (in English, well), he decides to test a problem and asks his uncle. After a long time thinking, Tolik's uncle hasn't any ideas on how to solve it. But, he doesn't want to tell Tolik about his inability to solve it, so he hasn't found anything better than asking you how to solve this task. In this task you are given a cell field n ⋅ m, consisting of n rows and m columns, where point's coordinates (x, y) mean it is situated in the x-th row and y-th column, considering numeration from one (1 ≤ x ≤ n, 1 ≤ y ≤ m). Initially, you stand in the cell (1, 1). Every move you can jump from cell (x, y), which you stand in, by any non-zero vector (dx, dy), thus you will stand in the (x+dx, y+dy) cell. Obviously, you can't leave the field, but also there is one more important condition — you're not allowed to use one vector twice. Your task is to visit each cell of the field exactly once (the initial cell is considered as already visited). Tolik's uncle is a very respectful person. Help him to solve this task! Input The first and only line contains two positive integers n, m (1 ≤ n ⋅ m ≤ 10^{6}) — the number of rows and columns of the field respectively. Output Print "-1" (without quotes) if it is impossible to visit every cell exactly once. Else print n ⋅ m pairs of integers, i-th from them should contain two integers x_i, y_i (1 ≤ x_i ≤ n, 1 ≤ y_i ≤ m) — cells of the field in order of visiting, so that all of them are distinct and vectors of jumps between them are distinct too. Notice that the first cell should have (1, 1) coordinates, according to the statement. Examples Input 2 3 Output 1 1 1 3 1 2 2 2 2 3 2 1 Input 1 1 Output 1 1 Note The vectors from the first example in the order of making jumps are (0, 2), (0, -1), (1, 0), (0, 1), (0, -2). Submitted Solution: ``` import math inp = input().split(' ') m = int(inp[0]) n = int(inp[1]) for column in range(1, math.ceil(m/2) + 1): rowRange = range(1, n + 1) if column == math.ceil(m / 2) and m % 2 == 1: rowRange = range(1, math.ceil(n/2) + 1) for row in rowRange: print(str(column) + ' ' + str(row)) if row == math.ceil(n/2) and n % 2 == 1: continue print(str(m + 1 - column) + ' ' + str(n + 1 - row)) ```
instruction
0
95,350
15
190,700
No
output
1
95,350
15
190,701
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,536
15
191,072
Tags: implementation Correct Solution: ``` n = int(input()) mat = [] for i in range(n): m_ = input() m_ = m_.split(' ') mat.append(m_) i = 0 s=0 m = int((n-1)/2) while i<n: if i != m: s += int(mat[i][i]) + int(mat[i][n-i-1]) + int(mat[i][m]) else: pass i += 1 i=0 while i<n: s+= int(mat[m][i]) i+=1 print(s) ```
output
1
95,536
15
191,073
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,537
15
191,074
Tags: implementation Correct Solution: ``` import time import collections class Time_test: def __enter__(self): self.enter_time = time.time() def __exit__(self, exc_type, exc_val, exc_tb): print("Command was executed in", time.time()-self.enter_time) n = int(input()) s = 0 for i in range(n): ipt = [int(x) for x in input().split()] if n//2 == i: s += sum(ipt) continue s += ipt[n//2] + ipt[i] + ipt[n-i-1] print(s) ```
output
1
95,537
15
191,075
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,538
15
191,076
Tags: implementation Correct Solution: ``` n=int(input()) k=[] sum1=0 sum2=0 sum3=0 sum4=0 for i in range(n): k.append(list(map(int,input().split()))) for i in range(len(k)): sum1=sum1+k[i][i] sum2=sum2+k[i][(len(k)-1)-i] sum3=sum3+k[int(len(k)/2)][i] sum4=sum4+k[i][int(len(k)/2)] j=k[int(len(k)/2)][int(len(k)/2)] x=sum1+sum2+sum3+sum4-3*j print(x) ```
output
1
95,538
15
191,077
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,539
15
191,078
Tags: implementation Correct Solution: ``` import sys def main(): inp = sys.stdin.read().strip().split('\n') n = int(inp[0]) m = [[int(x) for x in s.split()] for s in inp[1:]] s = sum(m[i][i] + m[i][-i-1] + m[i][n//2] + m[n//2][i] for i in range(n)) return s - 3*m[n//2][n//2] print(main()) ```
output
1
95,539
15
191,079
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,540
15
191,080
Tags: implementation Correct Solution: ``` N = int( input() ) mat = list( list( map( int, input().split() ) ) for i in range( N ) ) ans = 0 for i in range( N ): ans += mat[ i ][ i ] ans += mat[ N - 1 - i ][ i ] ans += mat[ N >> 1 ][ i ] ans += mat[ i ][ N >> 1 ] print( ans - mat[ N >> 1 ][ N >> 1 ] * 3 ) ```
output
1
95,540
15
191,081
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,541
15
191,082
Tags: implementation Correct Solution: ``` n = int(input()) grid = [] for i in range(n): row = [int(i) for i in input().split()] grid.append(row) sum = 0 for i in range(n): for j in range(n): if i == j or i == n - 1 - j or i == (n - 1) / 2 or j == (n - 1) / 2: sum += grid[i][j] print(sum) ```
output
1
95,541
15
191,083
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,542
15
191,084
Tags: implementation Correct Solution: ``` row=int(input()) matrix=[] for i in range(row): r=list(map(int, input().split())) matrix.append(r) p=row-1 count=0 for i in range(row): count += matrix[i][i] count += matrix[p-i][i] count += matrix[int(((p-1)/2)+1)][i] count += matrix[i][int(((p - 1) / 2) + 1)] count -= 3*matrix[int(((p-1)/2)+1)][int(((p-1)/2)+1)] print(count) ```
output
1
95,542
15
191,085
Provide tags and a correct Python 3 solution for this coding contest problem. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure.
instruction
0
95,543
15
191,086
Tags: implementation Correct Solution: ``` n = int(input()) matrix = [[int(j) for j in input().split()] for i in range(n)] summ=0 k=n//2 for i in range(n): for j in range(n): if i==j: summ = summ + matrix[i][j] elif i+j+1 ==n: summ = summ + matrix[i][j] elif i==k: summ = summ + matrix[i][j] elif j==k: summ = summ + matrix[i][j] print(summ) ```
output
1
95,543
15
191,087
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure. Submitted Solution: ``` n = int(input()) a = [] for i in range(n): a.append([int(i) for i in input().split()]) goodSum = 0 for i in range(n): goodSum += a[i][i] + a[i][n-1-i] + a[n//2][i] + a[i][n//2] print(goodSum - (3 * a[n//2][n//2])) ```
instruction
0
95,547
15
191,094
Yes
output
1
95,547
15
191,095
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The Smart Beaver from ABBYY got hooked on square matrices. Now he is busy studying an n × n size matrix, where n is odd. The Smart Beaver considers the following matrix elements good: * Elements of the main diagonal. * Elements of the secondary diagonal. * Elements of the "middle" row — the row which has exactly <image> rows above it and the same number of rows below it. * Elements of the "middle" column — the column that has exactly <image> columns to the left of it and the same number of columns to the right of it. <image> The figure shows a 5 × 5 matrix. The good elements are marked with green. Help the Smart Beaver count the sum of good elements of the given matrix. Input The first line of input data contains a single odd integer n. Each of the next n lines contains n integers aij (0 ≤ aij ≤ 100) separated by single spaces — the elements of the given matrix. The input limitations for getting 30 points are: * 1 ≤ n ≤ 5 The input limitations for getting 100 points are: * 1 ≤ n ≤ 101 Output Print a single integer — the sum of good matrix elements. Examples Input 3 1 2 3 4 5 6 7 8 9 Output 45 Input 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Output 17 Note In the first sample all matrix elements will be good. Good elements in the second sample are shown on the figure. Submitted Solution: ``` b=int(input()) a= [[int(j) for j in input().split()] for i in range(b)] print(a) sum=0 gum=0 rum=0 drum=0 d=int((b-1)/2) for i in range(b): sum=sum+a[d][i] gum=gum+a[i][d] for j in range(b): if(i==j): rum=rum+a[i][j] if((i+j)==b-1): drum=drum+a[i][j] c=int(sum+gum+rum+drum-(3*a[d][d])) print(c) ```
instruction
0
95,549
15
191,098
No
output
1
95,549
15
191,099
Provide tags and a correct Python 3 solution for this coding contest problem. Bajtek is learning to skate on ice. He's a beginner, so his only mode of transportation is pushing off from a snow drift to the north, east, south or west and sliding until he lands in another snow drift. He has noticed that in this way it's impossible to get from some snow drifts to some other by any sequence of moves. He now wants to heap up some additional snow drifts, so that he can get from any snow drift to any other one. He asked you to find the minimal number of snow drifts that need to be created. We assume that Bajtek can only heap up snow drifts at integer coordinates. Input The first line of input contains a single integer n (1 ≤ n ≤ 100) — the number of snow drifts. Each of the following n lines contains two integers xi and yi (1 ≤ xi, yi ≤ 1000) — the coordinates of the i-th snow drift. Note that the north direction coinсides with the direction of Oy axis, so the east direction coinсides with the direction of the Ox axis. All snow drift's locations are distinct. Output Output the minimal number of snow drifts that need to be created in order for Bajtek to be able to reach any snow drift from any other one. Examples Input 2 2 1 1 2 Output 1 Input 2 2 1 4 1 Output 0
instruction
0
96,401
15
192,802
Tags: brute force, dfs and similar, dsu, graphs Correct Solution: ``` #start the code from here n=int(input()) global parent parent=[i for i in range(n)] # n is total number of nodes # finding parent of a node def find(w): global parent if parent[w]==w: return w else: return find(parent[w]) def union(a,b): global parent w=find(a) y=find(b) if w==y: return parent[y]=w #start the code from here l=[] ans=0 for i in range(n): a,b=map(int,input().split()) for u in range(len(l)): if l[u][0]==a or l[u][1]==b: union(u,i) else: ans+=1 l.append([a,b]) pset=set() for i in range(len(l)): pset.add(find(i)) print(len(pset)-1) ```
output
1
96,401
15
192,803
Provide tags and a correct Python 3 solution for this coding contest problem. Bajtek is learning to skate on ice. He's a beginner, so his only mode of transportation is pushing off from a snow drift to the north, east, south or west and sliding until he lands in another snow drift. He has noticed that in this way it's impossible to get from some snow drifts to some other by any sequence of moves. He now wants to heap up some additional snow drifts, so that he can get from any snow drift to any other one. He asked you to find the minimal number of snow drifts that need to be created. We assume that Bajtek can only heap up snow drifts at integer coordinates. Input The first line of input contains a single integer n (1 ≤ n ≤ 100) — the number of snow drifts. Each of the following n lines contains two integers xi and yi (1 ≤ xi, yi ≤ 1000) — the coordinates of the i-th snow drift. Note that the north direction coinсides with the direction of Oy axis, so the east direction coinсides with the direction of the Ox axis. All snow drift's locations are distinct. Output Output the minimal number of snow drifts that need to be created in order for Bajtek to be able to reach any snow drift from any other one. Examples Input 2 2 1 1 2 Output 1 Input 2 2 1 4 1 Output 0
instruction
0
96,402
15
192,804
Tags: brute force, dfs and similar, dsu, graphs Correct Solution: ``` def dfs(node): vis[node]=1 for i in range(n): if (X[i]==X[node] or Y[i]==Y[node]) and vis[i]==0: dfs(i) r=[-1 for i in range(2005)] n=int(input()) X,Y=[],[] vis=[0]*101 for i in range(n): x,y=map(int,input().split()) X.append(x) Y.append(y) ans=0 for i in range(n): if (vis[i]==0): dfs(i) ans+=1 print(ans-1) ```
output
1
96,402
15
192,805