[Python] 프로그래머스 타깃넘버 & 백준 7576 토마토

#프로그래머스 타깃넘버

def solution(numbers, target):
    dfs(numbers, target, 0, 0)
    return

def dfs(numbers, target, now, index):
    global cnt
    if index == len(numbers):
        if now == target:
            cnt += 1
        return

    dfs(numbers, target, now + numbers[index], index+1) 
    dfs(numbers, target, now - numbers[index], index+1)

cnt = 0

from collections import deque
import sys

input = sys.stdin.readline
m, n = map(int, input().split())
graph = [list(map(int, input().split())) for _ in range(n)]

d_row = [0, -1, 0, 1] #시계 반대방향(오른쪽 위 왼쪽 아래)
d_col = [1, 0, -1, 0] #시계 반대방향(오른쪽 위 왼쪽 아래)

def bfs():
    queue = deque()
    for i in range(n):
        for j in range(m):
            if graph[i][j] == 1:
                queue.append([i, j])

    while queue:
        x ,y = queue.popleft()
        for d in range(4):
            nx = d_row[d] + x
            ny = d_col[d] + y
            if nx< 0 or ny < 0 or nx > n-1 or ny > m-1:
                continue
            if graph[nx][ny] == 0:
                graph[nx][ny] = graph[x][y] + 1
                queue.append([nx,ny])

bfs()
answer = 0
for i in range(n):
     for j in range(m):
         if graph[i][j] == 0:
             print(-1)
             exit()
         answer = max(answer, graph[i][j])
print(answer-1)#1부터 시작했으니깐 마지막 값에서 -1해주기