A83422.幅優先探索
普及/提高-
通过率：0%
时间限制：1.00s
内存限制：128MB
题目描述
一个大小为 n×m 的迷宫，你可以往上下左右任意方向移动 1 步，求最少需要多少步才能走出迷宫。
迷宫中 . 表示空地，# 表示墙壁，移动中只能穿过空地，不能穿墙。
输入格式
第 1 行 2 个正整数 n,m，表示迷宫有 n 行 m 列；
第 2 行 2 个正整数 sy,sx，表示起点坐标 (sy,sx);
第 3 行 2 个正整数 gy,gx，表示终点坐标 (gy,gx);
第 4 至 n+1 行，表示迷宫的俯视图
输出格式
输出最少需要多少步才能走出迷宫。（题目保证有解）
输入输出样例
输入#1
7 8 2 2 4 5 ######## #......# #.###### #..#...# #..##..# ##.....# ########
输出#1
11
输入#2
5 8 2 2 2 4 ######## #.#....# #.###..# #......# ########
输出#2
10
输入#3
50 50 2 2 49 49 ################################################## #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# #................................................# ##################################################
输出#3
94
说明/提示
对于 100% 的数据，1≤n,m≤50，sy,gy≤n，sx,gx≤m。