Submission #76264486

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Source Code Expand

from collections import deque

h, w = map(int, input().split())
grid = []
for i in range(h):
    grid.append(input())

dist = [[-1] * w for _ in range(h)]
q = deque()

for i in range(h):
    for j in range(w):
        if grid[i][j] == "#":
            dist[i][j] = 0
            q.append((i, j))

if not q:
    for _ in range(h):
        print('.' * w)
    exit()

if len(q) == h * w:
    for _ in range(h):
        print('.' * w)
    exit()

dirs = [(-1, -1), (-1, 0), (-1, 1), (0, -1), (0, 1), (1, -1), (1, 0), (1, 1)]

while q:
    r, c = q.popleft()
    for dr, dc in dirs:
        nr, nc = r + dr, c + dc
        if 0 <= nr < h and 0 <= nc < w and dist[nr][nc] == -1:
            dist[nr][nc] = dist[r][c] + 1
            q.append((nr, nc))

for i in range(h):
    ans = []
    for j in range(w):
        if dist[i][j] % 2 == 0:
            ans.append("#")
        else:
            ans.append(".")
    print("".join(ans))

Submission Info

Judge Result