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Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,010
15
14,020
Tags: implementation, math Correct Solution: ``` class CodeforcesTask436BSolution: def __init__(self): self.result = '' self.n_m_k = [] self.field = [] def read_input(self): self.n_m_k = [int(x) for x in input().split(" ")] for x in range(self.n_m_k[0]): self.field.append(input()) def process_task(self): result_row = [0 for x in range(self.n_m_k[1])] for x in range(self.n_m_k[0]): for y in range(self.n_m_k[1]): # print(x, y) field = self.field[x][y] if field == "R": pos = y + x if pos < self.n_m_k[1]: result_row[pos] += 1 elif field == "L": pos = y - x if pos >= 0: result_row[pos] += 1 elif field == "U" and not x % 2: result_row[y] += 1 self.result = " ".join([str(x) for x in result_row]) def get_result(self): return self.result if __name__ == "__main__": Solution = CodeforcesTask436BSolution() Solution.read_input() Solution.process_task() print(Solution.get_result()) ```
output
1
7,010
15
14,021
Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,011
15
14,022
Tags: implementation, math Correct Solution: ``` # -*- coding: utf-8 -*- import sys f = sys.stdin n, m, k = map(int, f.readline().strip().split()) s = f.readline().strip() sp = [0]*m for i in range(1, n): s = f.readline().strip() for l in range(m): if s[l]=='U': if i % 2 == 0: sp[l] += 1 elif s[l]=='R': mi = l+i if mi<m : sp[mi] += 1 elif s[l]=='L': mi = l-i if mi>=0 : sp[mi] += 1 #print(i, s, sp) print(' '.join([str(it) for it in sp])) ```
output
1
7,011
15
14,023
Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,012
15
14,024
Tags: implementation, math Correct Solution: ``` def f(): n, m, k = map(int, input().split()) s = [] a = [] for i in range(n): s.append(input()) for j in range(m): ans = 0 for i in range(n): if i + i < n and s[i + i][j] == 'U': ans += 1 if j - i >= 0 and s[i][j - i] == 'R': ans += 1 if j + i < m and s[i][j + i] == 'L': ans += 1 a.append(ans) print(' '.join(map(str, a))) f() ```
output
1
7,012
15
14,025
Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,013
15
14,026
Tags: implementation, math Correct Solution: ``` n, m, k = map(int, input().split()) field = [] counts = [] for j in range(m): counts.append(0) for i in range(n): row = list(input()) field.append(row) for i in range(n): for j in range(m): if field[i][j] == "L": jth = j - i if jth >= 0: counts[jth] += 1 elif field[i][j] == "R": jth = i + j if jth < m: counts[jth] += 1 elif field[i][j] == "U": if i % 2 == 0: counts[j] += 1 #counts = [] #for j in range(m): # count = 0 # for i in range(n): # if newfield[i][j] == "S": # count += 1 # counts.append(str(count)) #print(field) #print(newfield) print(" ".join(list(map(str, counts)))) ```
output
1
7,013
15
14,027
Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,014
15
14,028
Tags: implementation, math Correct Solution: ``` #!/usr/bin/python import re import inspect from sys import argv, exit def rstr(): return input() def rint(): return int(input()) def rints(splitchar=' '): return [int(i) for i in input().split(splitchar)] def varnames(obj, namespace=globals()): return [name for name in namespace if namespace[name] is obj] def pvar(var, override=False): prnt(varnames(var), var) def prnt(*args, override=False): if '-v' in argv or override: print(*args) class Spider(): def __init__(self, x, y, d): self.x = x self.y = y self.d = d def get_copy(self): return Spider(self.x, self.y, self.d) def move(self): if self.d == 'R': self.x += 1 elif self.d == 'L': self.x -= 1 elif self.d == 'U': self.y -= 1 elif self.d == 'D': self.y += 1 else: raise Exception('WHAT HAVE YOU DONE', self.d) def main(i, n, m, lders, rders, uders): sightings = 0 iders = [s for s in uders if s.x == i and s.y % 2 == 0] sightings += len(iders) prnt('id', len(iders)) ulders = [s for s in rders if s.y == (i - s.x)] sightings += len(ulders) prnt('uld', len(ulders)) urders = [s for s in lders if s.y == (s.x - i)] sightings += len(urders) prnt('urd', len(urders)) return str(sightings) if __name__ == '__main__': (n,m,k) = rints() field = [rstr() for i in range(n)] si = [0 for i in range(m)] spiders = [] for j,row in enumerate(field): for i,space in enumerate(row): if space == 'R': if i+j < len(si): si[i+j] += 1 if space == 'L': if i-j >= 0: si[i-j] += 1 if space == 'U': if j % 2 == 0: si[i] += 1 print(' '.join([str(i) for i in si])) ```
output
1
7,014
15
14,029
Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,015
15
14,030
Tags: implementation, math Correct Solution: ``` def solve(): answer = [0] * m for i in range(1, n): for j in range(m): if j - i >= 0: if park[i][j - i] == 'R': answer[j] += 1 if j + i < m: if park[i][j + i] == 'L': answer[j] += 1 if 2 * i < n: if park[2 * i][j] == 'U': answer[j] += 1 return answer n, m, k = tuple(map(int, input().split())) park = [input() for i in range(n)] print(' '.join(map(str, solve()))) ```
output
1
7,015
15
14,031
Provide tags and a correct Python 3 solution for this coding contest problem. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2.
instruction
0
7,016
15
14,032
Tags: implementation, math Correct Solution: ``` n, m, k = map(int, str.split(input())) f = tuple(map(lambda _: str.strip(input()), range(n))) r = [] for x in range(m): cr = sum(map(lambda y: f[y][x] == "U", range(0, n, 2))) for cx in range(max(0, x + 1 - n), x): cr += f[x - cx][cx] == "R" for cx in range(x + 1, min(m, n + x)): cr += f[cx - x][cx] == "L" r.append(cr) print(str.join(" ", map(str, r))) ```
output
1
7,016
15
14,033
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` n, m, k = map(int, input().split()) input() s = [0] * m for i in range(1, n): for j, x in enumerate(input()): if x == 'L': if j - i >= 0: s[j - i] += 1 elif x == 'R': if j + i < m: s[j + i] += 1 elif x == 'U' and i & 1 == 0: s[j] += 1 print(' '.join(map(str, s))) ```
instruction
0
7,017
15
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Yes
output
1
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14,035
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` I = lambda:map(int,input().split()) n,m,k = I() f = [['.' for _ in range(m)] for _ in range(n)] for i in range(n): s = input() for j in range(len(s)): if s[j] != '.': f[i][j] = s[j] ans = [0] * m for i in range(n): for j in range(m): if j - i >= 0 and f[i][j - i] == 'R': ans[j] += 1 if j + i < m and f[i][j + i] == 'L': ans[j] += 1 if f[0][j] == 'D': ans[j] += 1 if i + i < n and f[i + i][j] == 'U': ans[j] += 1 print (*ans) ```
instruction
0
7,018
15
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Yes
output
1
7,018
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` n, m, k = map( int, input().split() ) ans = [0] * m for i in range( n ): field = input() for j in range( m ): if ( field[j] == 'U' ) and ( i % 2 == 0 ): ans[j] += 1 elif ( field[j] == 'L' ) and ( j >= i ): ans[j - i] += 1 elif ( field[j] == 'R' ) and ( j + i < m ): ans[j + i] += 1 print ( ' '.join( map( str, ans ) ) ) ```
instruction
0
7,019
15
14,038
Yes
output
1
7,019
15
14,039
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` n, m, k = map( int, input().split() ) ans = [0] * m for i in range( n ): field = input() for j in range( m ): if ( field[j] == 'U' ) and ( i % 2 == 0 ): ans[j] += 1 elif ( field[j] == 'L' ) and ( j >= i ): ans[j - i] += 1 elif ( field[j] == 'R' ) and ( j + i < m ): ans[j + i] += 1 print ( ' '.join( map( str, ans ) ) ) # Made By Mostafa_Khaled ```
instruction
0
7,020
15
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Yes
output
1
7,020
15
14,041
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` class CodeforcesTask436BSolution: def __init__(self): self.result = '' self.n_m_k = [] self.field = [] def read_input(self): self.n_m_k = [int(x) for x in input().split(" ")] for x in range(self.n_m_k[0]): self.field.append(input()) def process_task(self): result_row = [0 for x in range(self.n_m_k[1])] for x in range(self.n_m_k[0]): for y in range(self.n_m_k[1]): # print(x, y) field = self.field[x][y] if field == "R": for j in range(y + x, min(self.n_m_k[1], y + 1 + x)): result_row[j] += 1 elif field == "L": for j in range(max(0, y - x), y): result_row[j] += 1 elif field == "U" and x > 1: result_row[y] += 1 self.result = " ".join([str(x) for x in result_row]) def get_result(self): return self.result if __name__ == "__main__": Solution = CodeforcesTask436BSolution() Solution.read_input() Solution.process_task() print(Solution.get_result()) ```
instruction
0
7,021
15
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No
output
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7,021
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` def f(): n, m, k = map(int, input().split()) a = [] for i in range(n): a.append(list(input().strip())) res = [0 for i in range(n)] for i in range(m): for j in range(1, n): if j >= i and a[j][i - j] == 'R': res[i] += 1 if j < n - i and a[j][i + j] == 'L': res[i] += 1 if j + j < m and a[j + j][i] == 'U': res[i] += 1 print(' '.join(list(map(str, res)))) f() ```
instruction
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7,022
15
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No
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. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` # -*- coding: utf-8 -*- import sys f = sys.stdin n, m, k = map(int, f.readline().strip().split()) sp = [0]*m for i in range(n): s = f.readline().strip() for l in range(m): if s[l]=='U' and i>1: sp[l] += 1 elif s[l]=='R': mi = l+i if mi<m : sp[mi] += 1 elif s[l]=='L': mi = l-i if mi>=0 : sp[mi] += 1 print(' '.join([str(it) for it in sp])) ```
instruction
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7,023
15
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No
output
1
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15
14,047
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all. <image> The park can be represented as a rectangular n × m field. The park has k spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time. Om Nom isn't yet sure where to start his walk from but he definitely wants: * to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); * to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park). We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries. Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. Input The first line contains three integers n, m, k (2 ≤ n, m ≤ 2000; 0 ≤ k ≤ m(n - 1)). Each of the next n lines contains m characters — the description of the park. The characters in the i-th line describe the i-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down). It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly k spiders. Output Print m integers: the j-th integer must show the number of spiders Om Nom will see if he starts his walk from the j-th cell of the first row. The cells in any row of the field are numbered from left to right. Examples Input 3 3 4 ... R.L R.U Output 0 2 2 Input 2 2 2 .. RL Output 1 1 Input 2 2 2 .. LR Output 0 0 Input 3 4 8 .... RRLL UUUU Output 1 3 3 1 Input 2 2 2 .. UU Output 0 0 Note Consider the first sample. The notes below show how the spider arrangement changes on the field over time: ... ... ..U ... R.L -> .*U -> L.R -> ... R.U .R. ..R ... Character "*" represents a cell that contains two spiders at the same time. * If Om Nom starts from the first cell of the first row, he won't see any spiders. * If he starts from the second cell, he will see two spiders at time 1. * If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. Submitted Solution: ``` n,m,k=map(int,input().split()) seen = [0 for _ in range(m)] for i in range(n): S = list(input()) for j in range(m): if S[j] == 'U': seen[j]+=1 elif S[j] == 'L' and j-i>=0: seen[j-i]+=1 elif S[j] == 'R' and j+i<m: seen[j+i]+=1 print(*seen, sep=" ") ```
instruction
0
7,024
15
14,048
No
output
1
7,024
15
14,049
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,403
15
16,806
Tags: graphs Correct Solution: ``` n,k=map(int,input().split()) arr=list(map(int,input().split())) dict1={} for i in range(1,n+1): dict1[i]=[] for i in range(k): dict1[arr[i]].append(i) ans=0 for i in range(1,n+1): if(i==1): if(n==1): break if(len(dict1[1])==0): ans+=2 else: if(len(dict1[2])==0): ans+=1 else: if(dict1[2][-1]<dict1[1][0]): ans+=1 elif(i==n): if(len(dict1[n])==0): ans+=2 else: if(len(dict1[n-1])==0): ans+=1 else: if(dict1[n-1][-1]<dict1[n][0]): ans+=1 else: if(len(dict1[i])==0): ans+=3 else: if(len(dict1[i-1])==0): ans+=1 else: if(dict1[i-1][-1]<dict1[i][0]): ans+=1 if(len(dict1[i+1])==0): ans+=1 else: if(dict1[i+1][-1]<dict1[i][0]): ans+=1 print(ans) ```
output
1
8,403
15
16,807
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,404
15
16,808
Tags: graphs Correct Solution: ``` import sys input = lambda: sys.stdin.readline().strip("\r\n") n, k = map(int, input().split()) x = list(map(int, input().split())) first = [k] * (n+1) last = [-1] * (n+1) for i in range(1, k+1): last[x[i-1]] = i for i in range(k, 0, -1): first[x[i-1]] = i ans = 0 # print(first) # print(last) for i in range(1, n+1): if last[i] == -1: ans += 1 for i in range(1, n): if first[i] >= last[i+1]: ans += 1 if first[i+1] >= last[i]: ans += 1 print(ans) ```
output
1
8,404
15
16,809
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,405
15
16,810
Tags: graphs Correct Solution: ``` import sys n, k = map(int, input().split()) q = list(map(int, input().split())) if n == 1: print(0) sys.exit() res = max(n - 2, 0) * 3 + 4 # # st = set(q) # res -= len(st) # # arr = [2] + [3] * max(n - 2, 0) + [2] arr = [0] * n l_flags = [False] * n r_flags = [False] * n for i in q: i -= 1 if arr[i] == 0: res -= 1 arr[i] += 1 if i > 0 and arr[i - 1] > 0 and not l_flags[i]: res -= 1 l_flags[i] = True if i < n - 1 and arr[i + 1] > 0 and not r_flags[i]: res -= 1 r_flags[i] = True print(res) ```
output
1
8,405
15
16,811
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,406
15
16,812
Tags: graphs Correct Solution: ``` from math import * from collections import * from bisect import * import sys input=sys.stdin.readline t=1 while(t): t-=1 n,k=map(int,input().split()) a=list(map(int,input().split())) vis=set() for i in a: vis.add((i,i)) if((i-1,i-1) in vis): vis.add((i-1,i)) if((i+1,i+1) in vis): vis.add((i+1,i)) r=n+(2*n)-2 print(r-len(vis)) ```
output
1
8,406
15
16,813
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,407
15
16,814
Tags: graphs Correct Solution: ``` def getn(): return int(input()) def getns(): return [int(x)for x in input().split()] # n=getn() # ns=getns() n,k=getns() ks=getns() f=[None]*(n+1) l=[None]*(n+1) ans=3*n-2 for i in range(k): c=ks[i] if f[c]==None: f[c]=i ans-=1 l[c]=i for i in range(1,n): if f[i]!=None and l[i+1]!=None and f[i]<l[i+1]: ans-=1 for i in range(2,n+1): if f[i]!=None and l[i-1]!=None and f[i]<l[i-1]: ans-=1 print(ans) ```
output
1
8,407
15
16,815
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,408
15
16,816
Tags: graphs Correct Solution: ``` def solve(): n,k = map(int,input().split()) x = list(map(int,input().split())) fpos = [k for i in range(n+1)] lpos = [-1 for i in range(n+1)] for i in range(1,k+1): lpos[x[i-1]] = i for i in range(k,0,-1): fpos[x[i-1]] = i ans = 0 for i in range(1,n+1): if lpos[i] == -1: ans+=1 # print(ans) for i in range(1,n): if fpos[i] >= lpos[i+1]: ans += 1 if fpos[i+1] >= lpos[i]: ans += 1 # print(i,i+1,ans) print(ans) if __name__ == '__main__': solve() ```
output
1
8,408
15
16,817
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,409
15
16,818
Tags: graphs Correct Solution: ``` (n,k)=[int(x) for x in input().split()] q =[int(x) for x in input().split()] f = 0 incl = set() counted={} for i in range(k-1,-1,-1): if q[i]+1 in incl and str(q[i])+"+1" not in counted: f+=1 counted[str(q[i])+"+1"]=True if q[i]-1 in incl and str(q[i])+"-1" not in counted: f+=1 counted[str(q[i])+"-1"]=True incl.add(q[i]) print(3*n-2-f-len(incl)) ```
output
1
8,409
15
16,819
Provide tags and a correct Python 3 solution for this coding contest problem. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios.
instruction
0
8,410
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16,820
Tags: graphs Correct Solution: ``` n, k = map(int, input().split()) a = list(map(int, input().split())) first_appear = {} last_appear = {} for i in range(k): last_appear[a[i]] = i for i in range(k)[::-1]: first_appear[a[i]] = i count = 0 for i in range(1,n+1): for j in range(i-1,i+2): if 1 <= j <= n: if i not in first_appear: count += 1 elif j not in last_appear: count += 1 else: if last_appear[j] < first_appear[i]: count += 1 print(count) ```
output
1
8,410
15
16,821
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` s = input().split() n = int(s[0]) k = int(s[1]) s = input().split() l = [int(x) for x in s] f = [False for i in range(n + 1)] for i in range(k): f[l[i]] = True ans = 0 L = [0 for i in range(n + 1)] R = [0 for i in range(n + 1)] for i in range(k): R[l[i]] = i for i in range(k - 1, -1, -1): L[l[i]] = i for i in range(1, n + 1): ans += not f[i] for i in range(1, n): if not f[i] or not f[i + 1]: ans += 2 continue if L[i] > R[i + 1]: ans += 1 if L[i + 1] > R[i]: ans += 1 print(ans) ```
instruction
0
8,411
15
16,822
Yes
output
1
8,411
15
16,823
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` from collections import defaultdict n, k = [int(item) for item in input().split()] x = [int(item) for item in input().split()] occ = defaultdict(list) for i in range(k): occ[x[i]].append(i) ans = 0 for i in range(1, n + 1): old = ans if not i in occ: if i == 1 or i == n: ans += 2 else: ans += 3 continue if i < n and (i + 1 not in occ or occ[i][0] > occ[i + 1][-1]): ans += 1 if i > 1 and (i - 1 not in occ or occ[i][0] > occ[i - 1][-1]): ans += 1 print(ans) ```
instruction
0
8,412
15
16,824
Yes
output
1
8,412
15
16,825
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` N,cnt=[int(1e5+5000),int(0)] class edg: pnt,nxt=[int(0),int(0)] fir=[0]*N ed=[edg()] for i in range(1,N): ed.append(edg()) def link(u,v): global cnt cnt+=1 ed[cnt].nxt=fir[u] fir[u]=cnt ed[cnt].pnt=v # print(ed[1].pnt,ed[2].pnt,ed[3].pnt) # print(cnt,ed[1].pnt,ed[1].nxt) # print(ed[2].pnt) #print(ed[0].pnt) n,k=list(map(int,input().split(" "))) #print(n," ",k) q=[0]+list(map(int,input().split(" "))) #print(q[1]) #link(1,1) #''' for i in range(1,k+1): # u,v=[1,1] u,v=[q[i],i] link(u,v) # print(u,v) #''' #stay ''' print(q) u=5 e=fir[u] print(ed[2].pnt) ''' ''' print(ed[2].pnt,ed[3].pnt) ed[2].pnt=1 print(ed[2].pnt,ed[3].pnt) ''' ans=int(0) for i in range(1,n+1): if(fir[i]==0): ans+=1 #left for i in range(2,n+1): minx,maxx=[(1<<27),-(1<<27)] u=i e=fir[u] while(e!=0): minx=min(minx,ed[e].pnt) e=ed[e].nxt u=i-1 e=fir[u] while(e!=0): maxx=max(maxx,ed[e].pnt) e=ed[e].nxt if(minx>maxx): ans+=1 # print(i,i-1) #right for i in range(1,n): minx,maxx=[(1<<27),-(1<<27)] u=i e=fir[u] while(e!=0): minx=min(minx,ed[e].pnt) e=ed[e].nxt u=i+1 e=fir[u] while(e!=0): maxx=max(maxx,ed[e].pnt) e=ed[e].nxt if(minx>maxx): ans+=1 # print(i,i+1) ''' if(i==4): # print(minx,maxx) u=i+1 e=fir[u] while(e!=0): print(ed[e].pnt) e=ed[e].nxt ''' print(ans) ```
instruction
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8,413
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16,826
Yes
output
1
8,413
15
16,827
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` n, k = map(int, input().split()) a = list(map(int, input().split())) count = (n - 1) * 2 + n b = [[0, -1] for i in range(n + 2)] c = set() for i in range(len(a)): if b[a[i] - 1][0] != 0 and b[a[i]][0] == 0: count -= 1 if b[a[i] + 1][0] != 0 and b[a[i]][0] == 0: count -= 1 if b[a[i]][0] == 0: count -= 1 l1 = (a[i] + 1, a[i]) l2 = (a[i], a[i] + 1) if b[a[i] + 1][1] > b[a[i]][1] and b[a[i] + 1][0] != 0 and b[a[i]][0] != 0 and l1 not in c and l2 not in c: count -= 1 c.add(l1) c.add(l2) l3 = (a[i], a[i] - 1) l4 = (a[i] - 1, a[i]) if b[a[i] - 1][1] > b[a[i]][1] and b[a[i] - 1][0] != 0 and b[a[i]][0] != 0 and l3 not in c and l4 not in c: count -= 1 c.add(l3) c.add(l4) b[a[i]][0] = 1 b[a[i]][1] = i print(count) ```
instruction
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8,414
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16,828
Yes
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1
8,414
15
16,829
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` n, k = map(int, input().split()) array = list(map(int, input().split())) d = {i: 0 for i in range(1, n + 1)} dind = {} ind = 1 for e in array: d[e] += 1 dind[e] = ind ind += 1 sum = 0 prooved = set() for i, x in enumerate(array): if x > 1 and (x, x - 1) not in prooved: if d[x - 1] == 0: sum += 1 prooved.add((x, x - 1)) else: if dind[x - 1] < i: sum += 1 prooved.add((x, x - 1)) if x < n: if d[x + 1] == 0 and (x, x + 1) not in prooved: sum += 1 prooved.add((x, x + 1)) else: if dind[x + 1] < i: sum += 1 prooved.add((x, x + 1)) for i in range(1, n+1): if d[i] == 0: sum += 1 if i != 1: sum += 1 if i != n: sum += 1 print(sum) ```
instruction
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8,415
15
16,830
No
output
1
8,415
15
16,831
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` n,k=map(int,input().split()) a=list(map(int,input().split())) d={i:0 for i in range(1,n+1)} for i in range(k): d[a[i]]+=i+1 s=0 #print(d) if(n==1): if(k==0): print(1) exit() else: print(0) exit() for i in range(1,n+1): if(d[i]==0): if(i==1)or(i==n): s+=2 else: s+=3 else: if(i==1): if(d[i]>d[i+1]): s+=1 elif(i==n): if(d[i]>d[i-1]): s+=1 else: if(d[i+1]>=d[i])and(d[i-1]>=d[i]): continue elif(d[i+1]<d[i])and(d[i-1]<d[i]): s+=2 else: s+=1 print(s) ```
instruction
0
8,416
15
16,832
No
output
1
8,416
15
16,833
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` from collections import defaultdict n,k=map(int,input().split()) ar=[int(x) for x in input().split()] d=defaultdict(int) for i in ar: d[i]+=1 ans=0 ok=False for i in range(1,n+1): if(i not in d): ans+=1 ok=True if(i<n): if(i not in d and i+1 not in d): ans+=2 prev=defaultdict(int) for i in ar: d[i]-=1 if(d[i]==0): d.pop(i) prev[i]+=1 if (i - 1 > 0 and i - 1 not in d): ans += 1 ok=True #print(i-1,i) if (i + 1 <= n and i + 1 not in d): ans += 1 ok=True #print(i,i+1) if(i-1>0 and i-1 not in d and i-1 not in prev): ans+=1 ok=True if(i+1<=n and i+1 not in d and i+1 not in prev): ans+=1 ok=True if(not ok): ans=0 break print(ans) ```
instruction
0
8,417
15
16,834
No
output
1
8,417
15
16,835
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Alice and Bob are playing a game on a line with n cells. There are n cells labeled from 1 through n. For each i from 1 to n-1, cells i and i+1 are adjacent. Alice initially has a token on some cell on the line, and Bob tries to guess where it is. Bob guesses a sequence of line cell numbers x_1, x_2, …, x_k in order. In the i-th question, Bob asks Alice if her token is currently on cell x_i. That is, Alice can answer either "YES" or "NO" to each Bob's question. At most one time in this process, before or after answering a question, Alice is allowed to move her token from her current cell to some adjacent cell. Alice acted in such a way that she was able to answer "NO" to all of Bob's questions. Note that Alice can even move her token before answering the first question or after answering the last question. Alice can also choose to not move at all. You are given n and Bob's questions x_1, …, x_k. You would like to count the number of scenarios that let Alice answer "NO" to all of Bob's questions. Let (a,b) denote a scenario where Alice starts at cell a and ends at cell b. Two scenarios (a_i, b_i) and (a_j, b_j) are different if a_i ≠ a_j or b_i ≠ b_j. Input The first line contains two integers n and k (1 ≤ n,k ≤ 10^5) — the number of cells and the number of questions Bob asked. The second line contains k integers x_1, x_2, …, x_k (1 ≤ x_i ≤ n) — Bob's questions. Output Print a single integer, the number of scenarios that let Alice answer "NO" to all of Bob's questions. Examples Input 5 3 5 1 4 Output 9 Input 4 8 1 2 3 4 4 3 2 1 Output 0 Input 100000 1 42 Output 299997 Note The notation (i,j) denotes a scenario where Alice starts at cell i and ends at cell j. In the first example, the valid scenarios are (1, 2), (2, 1), (2, 2), (2, 3), (3, 2), (3, 3), (3, 4), (4, 3), (4, 5). For example, (3,4) is valid since Alice can start at cell 3, stay there for the first three questions, then move to cell 4 after the last question. (4,5) is valid since Alice can start at cell 4, stay there for the first question, the move to cell 5 for the next two questions. Note that (4,5) is only counted once, even though there are different questions that Alice can choose to do the move, but remember, we only count each pair of starting and ending positions once. In the second example, Alice has no valid scenarios. In the last example, all (i,j) where |i-j| ≤ 1 except for (42, 42) are valid scenarios. Submitted Solution: ``` #Code by Sounak, IIESTS #------------------------------warmup---------------------------- import os import sys import math from io import BytesIO, IOBase from fractions import Fraction import collections from itertools import permutations from collections import defaultdict import threading 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,k=map(int,input().split()) first=[n]*max(n,k) last=[-1]*max(n,k) a=list(map(int,input().split())) for i in range (k): last[a[i]-1]=i if first[a[i]-1]==max(n,k): first[a[i]-1]=i c=0 for i in range (n): if first[i]==n: c+=1 if i!=n-1: if first[i+1]>=last[i]: c+=1 if i!=0: if first[i-1]>=last[i]: c+=1 print(c) ```
instruction
0
8,418
15
16,836
No
output
1
8,418
15
16,837
Provide tags and a correct Python 3 solution for this coding contest problem. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3
instruction
0
8,717
15
17,434
Tags: dfs and similar, dsu, graphs, number theory Correct Solution: ``` import math x, y = map(int, input().split()) x -= 1; y -= 1 print(math.gcd(x, y)+1) ```
output
1
8,717
15
17,435
Provide tags and a correct Python 3 solution for this coding contest problem. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3
instruction
0
8,718
15
17,436
Tags: dfs and similar, dsu, graphs, number theory Correct Solution: ``` n, m = map(int, input().split()) while 1 == 1: if n == m: print(n) break if n > m: n, m = m, n m -= (n - 1) ```
output
1
8,718
15
17,437
Provide tags and a correct Python 3 solution for this coding contest problem. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3
instruction
0
8,719
15
17,438
Tags: dfs and similar, dsu, graphs, number theory Correct Solution: ``` import math n,m=map(int,input().split()) print(math.gcd(n-1,m-1)+1) ```
output
1
8,719
15
17,439
Provide tags and a correct Python 3 solution for this coding contest problem. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3
instruction
0
8,720
15
17,440
Tags: dfs and similar, dsu, graphs, number theory Correct Solution: ``` n, m = map(int, input().split()) while True: if n == m: print(n) break if n > m: n, m = m, n m -= (n - 1) ```
output
1
8,720
15
17,441
Provide tags and a correct Python 3 solution for this coding contest problem. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3
instruction
0
8,721
15
17,442
Tags: dfs and similar, dsu, graphs, number theory Correct Solution: ``` from math import * n,m=sorted(list(map(int,input().split()))) print(1+gcd(n-1,m-n)) ```
output
1
8,721
15
17,443
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3 Submitted Solution: ``` import sys n, m = map(int, sys.stdin.readline().split()) def solve(n, m): if n == m: print(n) return if n > m: n,m = m,n if (m - 1) % (n - 1) == 0: print(n) return print(gcd(2*(n-1), 2*(m-1))) def gcd(a,b): if b < a: a,b = b,a while b % a != 0: a,b = b % a, a return a solve(n,m) ```
instruction
0
8,722
15
17,444
No
output
1
8,722
15
17,445
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3 Submitted Solution: ``` def solve(n, m): if n == m: print(n) return if n > m: n,m = m,n if (m - 1) % (n - 1) == 0: print(n) return print(gcd(2*(n-1), 2*(m-1))) def gcd(a,b): if b < a: a,b = b,a while b % a != 0: a,b = b % a, a return a ```
instruction
0
8,723
15
17,446
No
output
1
8,723
15
17,447
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3 Submitted Solution: ``` def solve(n, m): if n == m: return n if n > m: n,m = m,n if (m - 1) % (n - 1) == 0: return n return gcd(2*(n-1), 2*(m-1)) def gcd(a,b): if b < a: a,b = b,a while b % a != 0: a,b = b % a, a return a ```
instruction
0
8,724
15
17,448
No
output
1
8,724
15
17,449
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Let's imagine: there is a chess piece billiard ball. Its movements resemble the ones of a bishop chess piece. The only difference is that when a billiard ball hits the board's border, it can reflect from it and continue moving. More formally, first one of four diagonal directions is chosen and the billiard ball moves in that direction. When it reaches the square located on the board's edge, the billiard ball reflects from it; it changes the direction of its movement by 90 degrees and continues moving. Specifically, having reached a corner square, the billiard ball is reflected twice and starts to move the opposite way. While it moves, the billiard ball can make an infinite number of reflections. At any square of its trajectory the billiard ball can stop and on that the move is considered completed. <image> It is considered that one billiard ball a beats another billiard ball b if a can reach a point where b is located. You are suggested to find the maximal number of billiard balls, that pairwise do not beat each other and that can be positioned on a chessboard n × m in size. Input The first line contains two integers n and m (2 ≤ n, m ≤ 106). Output Print a single number, the maximum possible number of billiard balls that do not pairwise beat each other. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is preferred to use cin (also you may use the %I64d specificator). Examples Input 3 4 Output 2 Input 3 3 Output 3 Submitted Solution: ``` n,m=sorted(list(map(int,input().split()))) if n%(n-1)==m%(n-1): print(n) else: print(2) ```
instruction
0
8,725
15
17,450
No
output
1
8,725
15
17,451
Provide tags and a correct Python 3 solution for this coding contest problem. Joe has been hurt on the Internet. Now he is storming around the house, destroying everything in his path. Joe's house has n floors, each floor is a segment of m cells. Each cell either contains nothing (it is an empty cell), or has a brick or a concrete wall (always something one of three). It is believed that each floor is surrounded by a concrete wall on the left and on the right. Now Joe is on the n-th floor and in the first cell, counting from left to right. At each moment of time, Joe has the direction of his gaze, to the right or to the left (always one direction of the two). Initially, Joe looks to the right. Joe moves by a particular algorithm. Every second he makes one of the following actions: * If the cell directly under Joe is empty, then Joe falls down. That is, he moves to this cell, the gaze direction is preserved. * Otherwise consider the next cell in the current direction of the gaze. * If the cell is empty, then Joe moves into it, the gaze direction is preserved. * If this cell has bricks, then Joe breaks them with his forehead (the cell becomes empty), and changes the direction of his gaze to the opposite. * If this cell has a concrete wall, then Joe just changes the direction of his gaze to the opposite (concrete can withstand any number of forehead hits). Joe calms down as soon as he reaches any cell of the first floor. The figure below shows an example Joe's movements around the house. <image> Determine how many seconds Joe will need to calm down. Input The first line contains two integers n and m (2 ≤ n ≤ 100, 1 ≤ m ≤ 104). Next n lines contain the description of Joe's house. The i-th of these lines contains the description of the (n - i + 1)-th floor of the house — a line that consists of m characters: "." means an empty cell, "+" means bricks and "#" means a concrete wall. It is guaranteed that the first cell of the n-th floor is empty. Output Print a single number — the number of seconds Joe needs to reach the first floor; or else, print word "Never" (without the quotes), if it can never happen. Please, do not use the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier. Examples Input 3 5 ..+.# #+..+ +.#+. Output 14 Input 4 10 ...+.##+.+ +#++..+++# ++.#++++.. .+##.++#.+ Output 42 Input 2 2 .. ++ Output Never
instruction
0
9,380
15
18,760
Tags: brute force Correct Solution: ``` import sys from math import * def minp(): return sys.stdin.readline().strip() def mint(): return int(minp()) def mints(): return map(int, minp().split()) n, m = mints() a = list(minp()) x = 0 t = 0 d = 1 for i in range(n-1): b = list(minp()) l = x r = x wall = 0 while True: t += 1 if b[x] == '.': break if x + d == m or x + d < 0 or a[x+d] == '#': wall += 1 d = -d if wall == 2: print("Never") exit(0) elif a[x+d] == '+': wall = 0 a[x+d] = '.' d = -d elif l <= x+d and x+d <= r: if d == 1: t += r-x-1 x = r else: t += x-l-1 x = l else: x += d r = max(r,x) l = min(l,x) a, b = b, a print(t) ```
output
1
9,380
15
18,761
Provide tags and a correct Python 3 solution for this coding contest problem. Joe has been hurt on the Internet. Now he is storming around the house, destroying everything in his path. Joe's house has n floors, each floor is a segment of m cells. Each cell either contains nothing (it is an empty cell), or has a brick or a concrete wall (always something one of three). It is believed that each floor is surrounded by a concrete wall on the left and on the right. Now Joe is on the n-th floor and in the first cell, counting from left to right. At each moment of time, Joe has the direction of his gaze, to the right or to the left (always one direction of the two). Initially, Joe looks to the right. Joe moves by a particular algorithm. Every second he makes one of the following actions: * If the cell directly under Joe is empty, then Joe falls down. That is, he moves to this cell, the gaze direction is preserved. * Otherwise consider the next cell in the current direction of the gaze. * If the cell is empty, then Joe moves into it, the gaze direction is preserved. * If this cell has bricks, then Joe breaks them with his forehead (the cell becomes empty), and changes the direction of his gaze to the opposite. * If this cell has a concrete wall, then Joe just changes the direction of his gaze to the opposite (concrete can withstand any number of forehead hits). Joe calms down as soon as he reaches any cell of the first floor. The figure below shows an example Joe's movements around the house. <image> Determine how many seconds Joe will need to calm down. Input The first line contains two integers n and m (2 ≤ n ≤ 100, 1 ≤ m ≤ 104). Next n lines contain the description of Joe's house. The i-th of these lines contains the description of the (n - i + 1)-th floor of the house — a line that consists of m characters: "." means an empty cell, "+" means bricks and "#" means a concrete wall. It is guaranteed that the first cell of the n-th floor is empty. Output Print a single number — the number of seconds Joe needs to reach the first floor; or else, print word "Never" (without the quotes), if it can never happen. Please, do not use the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier. Examples Input 3 5 ..+.# #+..+ +.#+. Output 14 Input 4 10 ...+.##+.+ +#++..+++# ++.#++++.. .+##.++#.+ Output 42 Input 2 2 .. ++ Output Never
instruction
0
9,381
15
18,762
Tags: brute force Correct Solution: ``` n, m = [int(i) for i in input().split()] current_floor = list(input()) x, t, direction = 0, 0, 1 for i in range(n-1): floor = list(input()) l, r = x, x wall = 0 while True: t += 1 if floor[x] == '.': break if (x + direction == m) or (x + direction < 0) or (current_floor[x+direction] == '#'): wall += 1 direction = -direction if wall == 2: print("Never") exit(0) elif current_floor[x+direction] == '+': wall = 0 current_floor[x+direction] = '.' direction = -direction elif l <= x+direction and x+direction <= r: if direction == 1: t += r-x-1 x = r else: t += x-l-1 x = l else: x += direction r = max(r, x) l = min(l, x) current_floor, floor = floor, current_floor print(t) ```
output
1
9,381
15
18,763
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You have a grid with n rows and n columns. Each cell is either empty (denoted by '.') or blocked (denoted by 'X'). Two empty cells are directly connected if they share a side. Two cells (r1, c1) (located in the row r1 and column c1) and (r2, c2) are connected if there exists a sequence of empty cells that starts with (r1, c1), finishes with (r2, c2), and any two consecutive cells in this sequence are directly connected. A connected component is a set of empty cells such that any two cells in the component are connected, and there is no cell in this set that is connected to some cell not in this set. Your friend Limak is a big grizzly bear. He is able to destroy any obstacles in some range. More precisely, you can choose a square of size k × k in the grid and Limak will transform all blocked cells there to empty ones. However, you can ask Limak to help only once. The chosen square must be completely inside the grid. It's possible that Limak won't change anything because all cells are empty anyway. You like big connected components. After Limak helps you, what is the maximum possible size of the biggest connected component in the grid? Input The first line of the input contains two integers n and k (1 ≤ k ≤ n ≤ 500) — the size of the grid and Limak's range, respectively. Each of the next n lines contains a string with n characters, denoting the i-th row of the grid. Each character is '.' or 'X', denoting an empty cell or a blocked one, respectively. Output Print the maximum possible size (the number of cells) of the biggest connected component, after using Limak's help. Examples Input 5 2 ..XXX XX.XX X.XXX X...X XXXX. Output 10 Input 5 3 ..... .XXX. .XXX. .XXX. ..... Output 25 Note In the first sample, you can choose a square of size 2 × 2. It's optimal to choose a square in the red frame on the left drawing below. Then, you will get a connected component with 10 cells, marked blue in the right drawing. <image> Submitted Solution: ``` from collections import * c=ans=0 D=Counter() n,k=map(int,input().split()) a=[[-2]*(n+2)]+[[-2]+list(input())+[-2] for i in range(n)]+[[-2]*(n+2)] for i in range(n): for j in range(n): a[i+1][j+1]=-(a[i+1][j+1]=='X') def dfs(i,j): if a[i][j]: return a[i][j]=c; D[c]+=1 dfs(i-1,j); dfs(i+1,j) dfs(i,j-1); dfs(i,j+1) for i in range(n): for j in range(n): if a[i+1][j+1]==0: c+=1; dfs(i+1,j+1) for j in range(1,n-k+2): d,s=[0]*(c+3),set() for i in range(1,n+1): for y in range(k): d[a[i][j+y]+2]+=1 if d[a[i][j+y]+2]==1: s.add(a[i][j+y]+2) if i>k: for y in range(k): d[a[i-k][j+y]+2]-=1 if d[a[i][j+y]+2]==0: s.remove(a[i][j+y]+2) if i>=k: for q in range(k): s|={a[i+1][j+q]+2,a[i-k][j+q]+2,a[i-q][j-1]+2,a[i-q][j+k]+2} t=sum(D[key-2] for key in s-{0,1})+d[1] if t>ans: ans=t print(ans) ```
instruction
0
9,523
15
19,046
No
output
1
9,523
15
19,047
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You have a grid with n rows and n columns. Each cell is either empty (denoted by '.') or blocked (denoted by 'X'). Two empty cells are directly connected if they share a side. Two cells (r1, c1) (located in the row r1 and column c1) and (r2, c2) are connected if there exists a sequence of empty cells that starts with (r1, c1), finishes with (r2, c2), and any two consecutive cells in this sequence are directly connected. A connected component is a set of empty cells such that any two cells in the component are connected, and there is no cell in this set that is connected to some cell not in this set. Your friend Limak is a big grizzly bear. He is able to destroy any obstacles in some range. More precisely, you can choose a square of size k × k in the grid and Limak will transform all blocked cells there to empty ones. However, you can ask Limak to help only once. The chosen square must be completely inside the grid. It's possible that Limak won't change anything because all cells are empty anyway. You like big connected components. After Limak helps you, what is the maximum possible size of the biggest connected component in the grid? Input The first line of the input contains two integers n and k (1 ≤ k ≤ n ≤ 500) — the size of the grid and Limak's range, respectively. Each of the next n lines contains a string with n characters, denoting the i-th row of the grid. Each character is '.' or 'X', denoting an empty cell or a blocked one, respectively. Output Print the maximum possible size (the number of cells) of the biggest connected component, after using Limak's help. Examples Input 5 2 ..XXX XX.XX X.XXX X...X XXXX. Output 10 Input 5 3 ..... .XXX. .XXX. .XXX. ..... Output 25 Note In the first sample, you can choose a square of size 2 × 2. It's optimal to choose a square in the red frame on the left drawing below. Then, you will get a connected component with 10 cells, marked blue in the right drawing. <image> Submitted Solution: ``` cell = [] mcell = 0 ccell = 0 def grid(a,b,ni): global cell global mcell global ccell if a < 0 or b < 0 or a > mcell or b > mcell: return 0 if cell[a][b] == 'X': return 0 if cell[a][b] != '.': return 0 cell[a][b] = str(ni) ccell += 1 grid(a+1,b,ni) grid(a-1,b,ni) grid(a,b+1,ni) grid(a,b-1,ni) return 0 def checkgrid(i,j,k): global cell s = set() for t in range(k): r1 = cg(i-1,j+t) r2 = cg(i+k,j+t) r3 = cg(i+t,j-1) r4 = cg(i+t,j+k) if r1 != -1: s.add(r1) if r2 != -1: s.add(r2) if r3 != -1: s.add(r3) if r4 != -1: s.add(r4) return(list(s)) def cg(i,j): global cell if i < 0 or j < 0 or i > mcell or j > mcell: return -1 if cell[i][j] == 'X': return -1 return int(cell[i][j]) def cgc(i,j,k): global cell c = 0 for ii in range(k): for jj in range(k): if cell[i+ii][j+jj] == 'X': c += 1 return c n,k = [int(x) for x in input().split(' ')] mcell = n-1 for nn in range(n): cell.append(list(input())) ni = 0 mres = 0 cellcount = [] for i in range(n): for j in range(n): if cell[i][j] == '.': grid(i,j,ni) ni += 1 cellcount.append(ccell) ccell = 0 for i in range(n-k+1): for j in range(n-k+1): s = checkgrid(i,j,k) cc = 0 for ss in s: cc += cellcount[ss] cc += cgc(i,j,k) mres = max(mres,cc) print(mres) ```
instruction
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9,524
15
19,048
No
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1
9,524
15
19,049
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You have a grid with n rows and n columns. Each cell is either empty (denoted by '.') or blocked (denoted by 'X'). Two empty cells are directly connected if they share a side. Two cells (r1, c1) (located in the row r1 and column c1) and (r2, c2) are connected if there exists a sequence of empty cells that starts with (r1, c1), finishes with (r2, c2), and any two consecutive cells in this sequence are directly connected. A connected component is a set of empty cells such that any two cells in the component are connected, and there is no cell in this set that is connected to some cell not in this set. Your friend Limak is a big grizzly bear. He is able to destroy any obstacles in some range. More precisely, you can choose a square of size k × k in the grid and Limak will transform all blocked cells there to empty ones. However, you can ask Limak to help only once. The chosen square must be completely inside the grid. It's possible that Limak won't change anything because all cells are empty anyway. You like big connected components. After Limak helps you, what is the maximum possible size of the biggest connected component in the grid? Input The first line of the input contains two integers n and k (1 ≤ k ≤ n ≤ 500) — the size of the grid and Limak's range, respectively. Each of the next n lines contains a string with n characters, denoting the i-th row of the grid. Each character is '.' or 'X', denoting an empty cell or a blocked one, respectively. Output Print the maximum possible size (the number of cells) of the biggest connected component, after using Limak's help. Examples Input 5 2 ..XXX XX.XX X.XXX X...X XXXX. Output 10 Input 5 3 ..... .XXX. .XXX. .XXX. ..... Output 25 Note In the first sample, you can choose a square of size 2 × 2. It's optimal to choose a square in the red frame on the left drawing below. Then, you will get a connected component with 10 cells, marked blue in the right drawing. <image> Submitted Solution: ``` from collections import * c=ans=0 n,k=map(int,input().split()) a=[[-2]*(n+2)]+[[-2]+list(input())+[-2] for i in range(n)]+[[-2]*(n+2)] for i in range(n): for j in range(n): a[i+1][j+1]=-(a[i+1][j+1]=='X') D=[0]*(n*n+10) def dfs(i,j): l=r=j; u=d=i for t in range(j+1,n+2): r=t if a[i][t]: break for t in range(j-1,-1,-1): l=t if a[i][t]: break for t in range(i+1,n+2): d=t if a[t][j]: break for t in range(i-1,-1,-1): u=t if a[t][j]: break for t in range(j+1,r): D[c]+=1; a[i][t]=c for t in range(j-1,l,-1): D[c]+=1; a[i][t]=c for t in range(i+1,d): D[c]+=1; a[t][j]=c for t in range(i-1,u,-1): D[c]+=1; a[t][j]=c for t in range(j+1,r): dfs(i,t) for t in range(j-1,l,-1): dfs(i,t) for t in range(i+1,d): dfs(t,j) for t in range(i-1,u,-1): dfs(t,j) for i in range(n): for j in range(n): if a[i+1][j+1]==0: c+=1; D[c]+=1; a[i+1][j+1]=c; dfs(i+1,j+1) for x in a: print(x) for j in range(1,n-k+2): d=Counter() for i in range(1,n+1): for y in range(k): d[a[i][j+y]]+=1 if i>k: for y in range(k): d[a[i-k][j+y]]-=1 if d[a[i-k][j+y]]==0: del d[a[i-k][j+y]] if i>=k: s=set(d) for q in range(k): s|={a[i+1][j+q],a[i-k][j+q],a[i-q][j-1],a[i-q][j+k]} t=sum(D[key] for key in s-{-2,-1})+d[-1] if t>ans: ans=t print(ans) ```
instruction
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9,525
15
19,050
No
output
1
9,525
15
19,051
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You have a grid with n rows and n columns. Each cell is either empty (denoted by '.') or blocked (denoted by 'X'). Two empty cells are directly connected if they share a side. Two cells (r1, c1) (located in the row r1 and column c1) and (r2, c2) are connected if there exists a sequence of empty cells that starts with (r1, c1), finishes with (r2, c2), and any two consecutive cells in this sequence are directly connected. A connected component is a set of empty cells such that any two cells in the component are connected, and there is no cell in this set that is connected to some cell not in this set. Your friend Limak is a big grizzly bear. He is able to destroy any obstacles in some range. More precisely, you can choose a square of size k × k in the grid and Limak will transform all blocked cells there to empty ones. However, you can ask Limak to help only once. The chosen square must be completely inside the grid. It's possible that Limak won't change anything because all cells are empty anyway. You like big connected components. After Limak helps you, what is the maximum possible size of the biggest connected component in the grid? Input The first line of the input contains two integers n and k (1 ≤ k ≤ n ≤ 500) — the size of the grid and Limak's range, respectively. Each of the next n lines contains a string with n characters, denoting the i-th row of the grid. Each character is '.' or 'X', denoting an empty cell or a blocked one, respectively. Output Print the maximum possible size (the number of cells) of the biggest connected component, after using Limak's help. Examples Input 5 2 ..XXX XX.XX X.XXX X...X XXXX. Output 10 Input 5 3 ..... .XXX. .XXX. .XXX. ..... Output 25 Note In the first sample, you can choose a square of size 2 × 2. It's optimal to choose a square in the red frame on the left drawing below. Then, you will get a connected component with 10 cells, marked blue in the right drawing. <image> Submitted Solution: ``` from collections import * c=ans=0 D=Counter() n,k=map(int,input().split()) a=[[-2]*(n+2)]+[[-2]+list(input())+[-2] for i in range(n)]+[[-2]*(n+2)] for i in range(n): for j in range(n): a[i+1][j+1]=-(a[i+1][j+1]=='X') k+=2 def dfs(i,j): if a[i][j]: return a[i][j]=c; D[c]+=1 dfs(i-1,j); dfs(i+1,j) dfs(i,j-1); dfs(i,j+1) for i in range(n): for j in range(n): if a[i+1][j+1]==0: c+=1; dfs(i+1,j+1) for j in range(n-k+3): d=Counter() for i in range(n+2): for y in range(k): d[a[i][j+y]]+=1 if i>k-1: for y in range(k): d[a[i-k][j+y]]-=1 if i>=k-1: d[a[i+1-k][j]]-=1; d[a[i+1-k][j+k-2]]-=1; d[a[i][j]]-=1; d[a[i][j+k-2]]-=1 t=sum(D[key] for key in d if key>0 and d[key]>0)+d[-1] d[a[i+1-k][j]]+=1; d[a[i+1-k][j+k-2]]+=1; d[a[i][j]]+=1;d[a[i][j+k-2]]+=1 if t>ans: ans=t print(ans) ```
instruction
0
9,526
15
19,052
No
output
1
9,526
15
19,053
Provide a correct Python 3 solution for this coding contest problem. There is a pond with a rectangular shape. The pond is divided into a grid with H rows and W columns of squares. We will denote the square at the i-th row from the top and j-th column from the left by (i,\ j). Some of the squares in the pond contains a lotus leaf floating on the water. On one of those leaves, S, there is a frog trying to get to another leaf T. The state of square (i,\ j) is given to you by a character a_{ij}, as follows: * `.` : A square without a leaf. * `o` : A square with a leaf floating on the water. * `S` : A square with the leaf S. * `T` : A square with the leaf T. The frog will repeatedly perform the following action to get to the leaf T: "jump to a leaf that is in the same row or the same column as the leaf where the frog is currently located." Snuke is trying to remove some of the leaves, other than S and T, so that the frog cannot get to the leaf T. Determine whether this objective is achievable. If it is achievable, find the minimum necessary number of leaves to remove. Constraints * 2 ≤ H, W ≤ 100 * a_{ij} is `.`, `o`, `S` or `T`. * There is exactly one `S` among a_{ij}. * There is exactly one `T` among a_{ij}. Input Input is given from Standard Input in the following format: H W a_{11} ... a_{1W} : a_{H1} ... a_{HW} Output If the objective is achievable, print the minimum necessary number of leaves to remove. Otherwise, print `-1` instead. Examples Input 3 3 S.o .o. o.T Output 2 Input 3 4 S... .oo. ...T Output 0 Input 4 3 .S. .o. .o. .T. Output -1 Input 10 10 .o...o..o. ....o..... ....oo.oo. ..oooo..o. ....oo.... ..o..o.... o..o....So o....T.... ....o..... ........oo Output 5
instruction
0
9,737
15
19,474
"Correct Solution: ``` from collections import deque INF = float("inf") TO = 0; CAP = 1; REV = 2 class Dinic: def __init__(self, N): self.N = N self.V = [[] for _ in range(N)] # to, cap, rev # 辺 e = V[n][m] の逆辺は V[e[TO]][e[REV]] self.level = [0] * N def add_edge(self, u, v, cap): self.V[u].append([v, cap, len(self.V[v])]) self.V[v].append([u, 0, len(self.V[u])-1]) def add_edge_undirected(self, u, v, cap): # 未検証 self.V[u].append([v, cap, len(self.V[v])]) self.V[v].append([u, cap, len(self.V[u])-1]) def bfs(self, s: int) -> bool: self.level = [-1] * self.N self.level[s] = 0 q = deque() q.append(s) while len(q) != 0: v = q.popleft() for e in self.V[v]: if e[CAP] > 0 and self.level[e[TO]] == -1: # capが1以上で未探索の辺 self.level[e[TO]] = self.level[v] + 1 q.append(e[TO]) return True if self.level[self.g] != -1 else False # 到達可能 def dfs(self, v: int, f) -> int: if v == self.g: return f for i in range(self.ite[v], len(self.V[v])): self.ite[v] = i e = self.V[v][i] if e[CAP] > 0 and self.level[v] < self.level[e[TO]]: d = self.dfs(e[TO], min(f, e[CAP])) if d > 0: # 増加路 e[CAP] -= d # cap を減らす self.V[e[TO]][e[REV]][CAP] += d # 反対方向の cap を増やす return d return 0 def solve(self, s, g): self.g = g flow = 0 while self.bfs(s): # 到達可能な間 self.ite = [0] * self.N f = self.dfs(s, INF) while f > 0: flow += f f = self.dfs(s, INF) return flow H, W = map(int, input().split()) dinic = Dinic(H+W+2) for i in range(H): a = input() for j, a_ in enumerate(a): if a_=="S": start = i, j elif a_=="T": goal = i, j if a_!=".": dinic.add_edge_undirected(H + j, i, 1) dinic.add_edge_undirected(H+W, start[0], 1<<30) dinic.add_edge_undirected(H+W, start[1]+H, 1<<30) dinic.add_edge_undirected(H+W+1, goal[0], 1<<30) dinic.add_edge_undirected(H+W+1, goal[1]+H, 1<<30) if start[0]==goal[0] or start[1]==goal[1]: print(-1) else: print(dinic.solve(H+W, H+W+1)) ```
output
1
9,737
15
19,475
Provide a correct Python 3 solution for this coding contest problem. There is a pond with a rectangular shape. The pond is divided into a grid with H rows and W columns of squares. We will denote the square at the i-th row from the top and j-th column from the left by (i,\ j). Some of the squares in the pond contains a lotus leaf floating on the water. On one of those leaves, S, there is a frog trying to get to another leaf T. The state of square (i,\ j) is given to you by a character a_{ij}, as follows: * `.` : A square without a leaf. * `o` : A square with a leaf floating on the water. * `S` : A square with the leaf S. * `T` : A square with the leaf T. The frog will repeatedly perform the following action to get to the leaf T: "jump to a leaf that is in the same row or the same column as the leaf where the frog is currently located." Snuke is trying to remove some of the leaves, other than S and T, so that the frog cannot get to the leaf T. Determine whether this objective is achievable. If it is achievable, find the minimum necessary number of leaves to remove. Constraints * 2 ≤ H, W ≤ 100 * a_{ij} is `.`, `o`, `S` or `T`. * There is exactly one `S` among a_{ij}. * There is exactly one `T` among a_{ij}. Input Input is given from Standard Input in the following format: H W a_{11} ... a_{1W} : a_{H1} ... a_{HW} Output If the objective is achievable, print the minimum necessary number of leaves to remove. Otherwise, print `-1` instead. Examples Input 3 3 S.o .o. o.T Output 2 Input 3 4 S... .oo. ...T Output 0 Input 4 3 .S. .o. .o. .T. Output -1 Input 10 10 .o...o..o. ....o..... ....oo.oo. ..oooo..o. ....oo.... ..o..o.... o..o....So o....T.... ....o..... ........oo Output 5
instruction
0
9,738
15
19,476
"Correct Solution: ``` import sys sys.setrecursionlimit(1000000) def FF(E, s, t): NN = H+W+2 G = [[] for _ in range(NN)] for a, b, f in E: G[a].append([b, f, len(G[b])]) G[b].append([a, 0, len(G[a])-1]) def dfs(s, t, f): if s == t: return f used[s] = 1 for i, (b, _f, r) in enumerate(G[s]): if used[b] or _f == 0: continue d = dfs(b, t, min(f, _f)) if d > 0: G[s][i][1] -= d G[b][r][1] += d return d return 0 flow = 0 while 1: used = [0] * NN f = dfs(s, t, 10**100) if f == 0: return flow flow += f E = [] H, W = map(int, input().split()) for i in range(H): A = input() for j in range(W): if A[j] == "o": E.append((i, j+H, 1)) E.append((j+H, i, 1)) elif A[j] == "S": S = (i, j+H) elif A[j] == "T": T = (i, j+H) E.append((H+W, S[0], 10**6)) E.append((H+W, S[1], 10**6)) E.append((T[0], H+W+1, 10**6)) E.append((T[1], H+W+1, 10**6)) ff = FF(E, H+W, H+W+1) print(ff if ff < 10**6 else -1) ```
output
1
9,738
15
19,477
Provide a correct Python 3 solution for this coding contest problem. There is a pond with a rectangular shape. The pond is divided into a grid with H rows and W columns of squares. We will denote the square at the i-th row from the top and j-th column from the left by (i,\ j). Some of the squares in the pond contains a lotus leaf floating on the water. On one of those leaves, S, there is a frog trying to get to another leaf T. The state of square (i,\ j) is given to you by a character a_{ij}, as follows: * `.` : A square without a leaf. * `o` : A square with a leaf floating on the water. * `S` : A square with the leaf S. * `T` : A square with the leaf T. The frog will repeatedly perform the following action to get to the leaf T: "jump to a leaf that is in the same row or the same column as the leaf where the frog is currently located." Snuke is trying to remove some of the leaves, other than S and T, so that the frog cannot get to the leaf T. Determine whether this objective is achievable. If it is achievable, find the minimum necessary number of leaves to remove. Constraints * 2 ≤ H, W ≤ 100 * a_{ij} is `.`, `o`, `S` or `T`. * There is exactly one `S` among a_{ij}. * There is exactly one `T` among a_{ij}. Input Input is given from Standard Input in the following format: H W a_{11} ... a_{1W} : a_{H1} ... a_{HW} Output If the objective is achievable, print the minimum necessary number of leaves to remove. Otherwise, print `-1` instead. Examples Input 3 3 S.o .o. o.T Output 2 Input 3 4 S... .oo. ...T Output 0 Input 4 3 .S. .o. .o. .T. Output -1 Input 10 10 .o...o..o. ....o..... ....oo.oo. ..oooo..o. ....oo.... ..o..o.... o..o....So o....T.... ....o..... ........oo Output 5
instruction
0
9,739
15
19,478
"Correct Solution: ``` # https://tjkendev.github.io/procon-library/python/max_flow/dinic.html # Dinic's algorithm from collections import deque class Dinic: def __init__(self, N): self.N = N self.G = [[] for i in range(N)] def add_edge(self, fr, to, cap): forward = [to, cap, None] forward[2] = backward = [fr, 0, forward] self.G[fr].append(forward) self.G[to].append(backward) def add_multi_edge(self, v1, v2, cap1, cap2): edge1 = [v2, cap1, None] edge1[2] = edge2 = [v1, cap2, edge1] self.G[v1].append(edge1) self.G[v2].append(edge2) def bfs(self, s, t): self.level = level = [None]*self.N deq = deque([s]) level[s] = 0 G = self.G while deq: v = deq.popleft() lv = level[v] + 1 for w, cap, _ in G[v]: if cap and level[w] is None: level[w] = lv deq.append(w) return level[t] is not None def dfs(self, v, t, f): if v == t: return f level = self.level for e in self.it[v]: w, cap, rev = e if cap and level[v] < level[w]: d = self.dfs(w, t, min(f, cap)) if d: e[1] -= d rev[1] += d return d return 0 def flow(self, s, t): flow = 0 INF = 10**9 + 7 G = self.G while self.bfs(s, t): *self.it, = map(iter, self.G) f = INF while f: f = self.dfs(s, t, INF) flow += f return flow # coding: utf-8 # Your code here! import sys read = sys.stdin.read readline = sys.stdin.readline h,w = map(int,readline().split()) b = read().split() #g = [[] for _ in range(h+w+2)] S = h+w T = h+w+1 D = Dinic(h+w+2) for i in range(h): for j in range(w): if b[i][j] == "S": #print("S") sh,sw = i,j D.add_edge(S, i, 200) D.add_edge(S, j+h, 200) #g[S].append((i,200)) #g[S].append((j+h,200)) elif b[i][j] == "T": #print("T") th,tw = i,j D.add_edge(i, T, 200) D.add_edge(j+h, T, 200) #g[i].append((T,200)) #g[j+h].append((T,200)) elif b[i][j] == "o": #print("o") D.add_edge(i, j+h, 1) D.add_edge(j+h, i, 1) #g[i].append((j+h,1)) #g[j+h].append((i,1)) if sh==th or sw==tw: print(-1) else: print(D.flow(S,T)) ```
output
1
9,739
15
19,479
Provide a correct Python 3 solution for this coding contest problem. There is a pond with a rectangular shape. The pond is divided into a grid with H rows and W columns of squares. We will denote the square at the i-th row from the top and j-th column from the left by (i,\ j). Some of the squares in the pond contains a lotus leaf floating on the water. On one of those leaves, S, there is a frog trying to get to another leaf T. The state of square (i,\ j) is given to you by a character a_{ij}, as follows: * `.` : A square without a leaf. * `o` : A square with a leaf floating on the water. * `S` : A square with the leaf S. * `T` : A square with the leaf T. The frog will repeatedly perform the following action to get to the leaf T: "jump to a leaf that is in the same row or the same column as the leaf where the frog is currently located." Snuke is trying to remove some of the leaves, other than S and T, so that the frog cannot get to the leaf T. Determine whether this objective is achievable. If it is achievable, find the minimum necessary number of leaves to remove. Constraints * 2 ≤ H, W ≤ 100 * a_{ij} is `.`, `o`, `S` or `T`. * There is exactly one `S` among a_{ij}. * There is exactly one `T` among a_{ij}. Input Input is given from Standard Input in the following format: H W a_{11} ... a_{1W} : a_{H1} ... a_{HW} Output If the objective is achievable, print the minimum necessary number of leaves to remove. Otherwise, print `-1` instead. Examples Input 3 3 S.o .o. o.T Output 2 Input 3 4 S... .oo. ...T Output 0 Input 4 3 .S. .o. .o. .T. Output -1 Input 10 10 .o...o..o. ....o..... ....oo.oo. ..oooo..o. ....oo.... ..o..o.... o..o....So o....T.... ....o..... ........oo Output 5
instruction
0
9,740
15
19,480
"Correct Solution: ``` from collections import deque class mf_graph: n=1 g=[[] for i in range(1)] pos=[] def __init__(self,N): self.n=N self.g=[[] for i in range(N)] def add_edge(self,From,To,cap): assert 0<=From and From<self.n assert 0<=To and To<self.n assert 0<=cap m=len(self.pos) self.pos.append((From,len(self.g[From]))) self.g[From].append({"to":To,"rev":len(self.g[To]),"cap":cap}) self.g[To].append({"to":From,"rev":len(self.g[From])-1,"cap":0}) return m def get_edge(self,i): m=len(self.pos) assert 0<=i and i<m _e=self.g[self.pos[i][0]][self.pos[i][1]] _re=self.g[_e["to"]][_e["rev"]] return {"from":self.pos[i][0], "to":_e["to"], "cap":_e["cap"]+_re["cap"], "flow":_re["cap"]} def edges(self): m=len(self.pos) result=[] for i in range(m): result.append(self.get_edge(i)) return result def change_edge(self,i,new_cap,new_flow): m=len(self.pos) assert 0<=i and i<m assert 0<=new_flow and new_flow<=new_cap _e=self.g[self.pos[i][0]][self.pos[i][1]] _re=self.g[_e["to"]][_e["rev"]] _e["cap"]=new_cap-new_flow _re["cap"]=new_flow def flow(self,s,t,flow_limit=(2**31)-1): assert 0<=s and s<self.n assert 0<=t and t<self.n level=[0 for i in range(self.n)] Iter=[0 for i in range(self.n)] que=deque([]) def bfs(): for i in range(self.n): level[i]=-1 level[s]=0 que=deque([]) que.append(s) while(len(que)>0): v=que.popleft() for e in self.g[v]: if e["cap"]==0 or level[e["to"]]>=0:continue level[e["to"]]=level[v]+1 if e["to"]==t:return que.append(e["to"]) def dfs(func,v,up): if (v==s):return up res=0 level_v=level[v] for i in range(Iter[v],len(self.g[v])): e=self.g[v][i] if (level_v<=level[e["to"]] or self.g[e["to"]][e["rev"]]["cap"]==0):continue d=func(func,e["to"],min(up-res,self.g[e["to"]][e["rev"]]["cap"])) if d<=0:continue self.g[v][i]["cap"]+=d self.g[e["to"]][e["rev"]]["cap"]-=d res+=d if res==up:break return res flow=0 while(flow<flow_limit): bfs() if level[t]==-1: break for i in range(self.n): Iter[i]=0 while(flow<flow_limit): f=dfs(dfs,t,flow_limit-flow) if not(f):break flow+=f return flow def min_cut(self,s): visited=[False for i in range(self.n)] que=deque([]) que.append(s) while(len(que)>0): p=que.popleft() visited[p]=True for e in self.g[p]: if e["cap"] and not(visited[e["to"]]): visited[e["to"]]=True que.append(e["to"]) return visited H,W=map(int,input().split()) a=[list(input()) for i in range(H)] G=mf_graph(H+W+2) INF=10**9 s=H+W t=H+W+1 for i in range(H): for j in range(W): if a[i][j]=="S": G.add_edge(s,i,INF) G.add_edge(s,j+H,INF) if a[i][j]=="T": G.add_edge(i,t,INF) G.add_edge(j+H,t,INF) if a[i][j]!=".": G.add_edge(i,j+H,1) G.add_edge(j+H,i,1) ans=G.flow(s,t) if ans>=INF: print(-1) else: print(ans) ```
output
1
9,740
15
19,481