63 lines
2.2 KiB
Python
63 lines
2.2 KiB
Python
class Solution:
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def solve(self, board: List[List[str]]) -> None:
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"""
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Do not return anything, modify board in-place instead.
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"""
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que = []
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front = -1
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tail = -1
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def push_back(que, front, tail, ele):
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lq = len(que)
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tail += 1
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if lq <= tail:
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que.append(ele)
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else:
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que[tail] = ele
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return tail
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def pop(que, front, tail):
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front += 1
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return (que[front], front)
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d = [(1,0),(-1,0),(0,1),(0,-1)]
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height = len(board)
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width = len(board[0])
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def is_valid(x, y):
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if x<0 or y < 0 or x >= height or y >= width:
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return False
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return True
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is_visited = []
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for x, l in enumerate(board):
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is_visited.append([])
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for y in l:
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is_visited[x].append(0)
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if height < 3 or width < 3:
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return board
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def is_edge(x, y):
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if x == 0 or y == 0 or x == height - 1 or y == width - 1:
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return True
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return False
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for x in range(1,height - 1):
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for y in range(1,width - 1):
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if board[x][y] == 'X' or is_visited[x][y] == 1: continue
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tail = push_back(que,front, tail,(x,y))
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flag = 0
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last_front = front
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while front != tail:
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(top_ele, front) = pop(que, front, tail)
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for (cx, cy) in d:
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nx = cx + top_ele[0]
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ny = cy + top_ele[1]
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if is_edge(nx, ny):
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if board[nx][ny] == 'O':
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flag = 1
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continue
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if board[nx][ny] == 'O' and is_visited[nx][ny]==0:
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tail = push_back(que,front,tail,(nx,ny))
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is_visited[nx][ny]=1
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if flag == 0:
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for idx in range(last_front + 1, front + 1):
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xx = que[idx][0]
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yy = que[idx][1]
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board[xx][yy]='X'
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return board
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