from collections import deque import sys input = sys.stdin.readline n,m = map(int, input().split()) map = [list(map(int, input().strip())) for _ in range(n)] dx = [1,0,-1,0] dy = [0,1,0,-1] def bfs(y,x): q=deque() q.append((y,x)) cnt = 0 while q: ey, ex = q.popleft() for k in range(4): xx = dx[k] + ex yy = dy[k] + ey if 0