Python BFS 迷宫问题

import queue
print("Please input the size of the square:")
n = int(input())
map_ = [([0]*n) for i in range(n)] #创建地图
vis = [([0]*n) for i in range(n)] #访问标记
front = [([0]*n) for i in range(n)] #路径
s,t = [0,0],[n-1,n-1] #初始化猫(s)鼠(t)位置
xPos = [1,0,-1,0] # x坐标方向
yPos = [0,1,0,-1] # y坐标方向


def bfs(x,y):
    q = queue.Queue()
    q.put([x,y])
    vis[x][y]=1
    while q.qsize() != 0:
        now = q.get()
        if now == [n-1,n-1]:
            return
        for i in range(0,4):
            xx = now[0] + xPos[i]
            yy = now[1] + yPos[i]
            if xx<0 or xx>n-1 or yy<0 or yy>n-1:
                continue
            elif map_[xx][yy] == 1 or vis[xx][yy]==1:
                continue
            else:
                q.put([xx,yy])
                vis[xx][yy]=1
                front[xx][yy]=now # 记录上一次的位置
    return

def printRoad():
    q = queue.LifoQueue() #栈
    now=[n-1,n-1]
    while now != [0,0]:
        # print(now)
        q.put(now)
        now = front[now[0]][now[1]]
    print("The road：")
    while q.qsize():
        temp = q.get()
        print(temp)

for i in range(n):
    map_[i] = input().split(" ")

map_[0][0]='S' #标记猫位置
map_[n-1][n-1]='T' #标记鼠位置
# print(vis)
# print(map_[1][0])
# print(vis[1][0])

bfs(0,0)
printRoad()

# 输入
# S 代表起点（猫的位置）T代表终点（鼠的位置）
# 1 代表有路障， 0代表没有
'''
input: 
6
S 0 0 0 0 0
0 0 0 0 1 0
0 1 0 0 1 1
0 1 0 0 0 0
0 1 0 1 0 0
0 0 0 0 0 T
'''