import sys
sys.setrecursionlimit(10**6)

H, W = map(int, input().split())
grid = [list(input()) for _ in range(H)]

dx = [1, -1, 0, 0]
dy = [0, 0, 1, -1]

visited = [[False] * W for _ in range(H)]

def dfs(x, y, char):
    stack = [(x, y)]
    component = [(x, y)]
    visited[x][y] = True
    while stack:
        cx, cy = stack.pop()
        for i in range(4):
            nx, ny = cx + dx[i], cy + dy[i]
            if 0 <= nx < H and 0 <= ny < W and not visited[nx][ny] and grid[nx][ny] == char:
                visited[nx][ny] = True
                stack.append((nx, ny))
                component.append((nx, ny))
    return component

for i in range(H):
    for j in range(W):
        if grid[i][j] != '.' and not visited[i][j]:
            component = dfs(i, j, grid[i][j])
            if len(component) >= 4:
                for x, y in component:
                    grid[x][y] = '.'

for row in grid:
    print(''.join(row))