BOJ - 14940 - 쉬운 최단거리

import sys
from collections import deque

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

def BFS(matrix, i, j, N, M):
    dq = deque()
    dq.append((i, j))


    while dq:
        x, y = dq.popleft()
        for k in range(4):
            nx, ny = x + dx[k], y + dy[k]

            if 0 <= nx < N and 0 <= ny < M and matrix[nx][ny] == 1:
                dq.append((nx, ny))
                matrix[nx][ny] = matrix[x][y] + 1



def solution():
    N, M = map(int, sys.stdin.readline().split())
    matrix = []

    for _ in range(N):
        matrix.append(list(map(int, sys.stdin.readline().split())))

    x, y = -1, -1
    for i in range(N):
        for j in range(M):
            if matrix[i][j] == 2:
                x, y = i, j

    BFS(matrix, x, y, N, M)

    for i in range(N):
        for j in range(M):
            v = matrix[i][j]
            print("%d" % (v - 2 if v else 0), end=' ')
        print()

solution()

https://www.acmicpc.net/problem/14940