bj_5212.py

import sys
import copy

sys.stdin = open('bj_5212_in.txt', 'r')
input = sys.stdin.readline

r, c = map(int, input().strip().split())
sea = [['.']*(c+2)]

for _ in range(r):
    sea.append(list('.'+input().strip()+'.'))

sea.append(['.']*(c+2))
copy_map = copy.deepcopy(sea)
# print(copy_map)
direction = [(-1, 0), (0, 1), (+1, 0), (0, -1)]

for row in range(1, r+1): #행
    for col in range(1, c+1): #열
        if sea[row][col] == 'X': #육지면
            cnt = 0
            for dr, dc in direction: #상하좌우 확인
                n_row = row + dr
                n_col = col + dc
                if sea[n_row][n_col] == '.': cnt += 1
            if cnt >= 3:
                copy_map[row][col] = '.'
        else:
            continue

# print(copy_map)

#직사각형 범위 찾기
up = 999
down = 0
left = 999
right = 0
for row in range(1, r+1): #행
    for col in range(1, c+1): #열
        if copy_map[row][col] == 'X':
            up = min(up, row)
            down = max(down, row)
            left = min(left, col)
            right = max(right, col)

# print(up, down, left, right)

for row in range(up, down+1): #행
    for col in range(left, right+1): #열
        print(copy_map[row][col], end='')
    print()