迷宫问题，求最短路径长度、最短路径条数、所有最短路径，DFS+BFS+栈+队列

一组测试数据得到的结果

8 8 3
3 3
4 5
6 6
2 1
7 7

最短路径   1 :
(2, 1) (3, 1) (4, 1) (5, 1) (6, 1) (7, 1) (7, 2) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   2 :
(2, 1) (3, 1) (4, 1) (5, 1) (6, 1) (6, 2) (7, 2) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   3 :
(2, 1) (3, 1) (4, 1) (5, 1) (6, 1) (6, 2) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   4 :
(2, 1) (3, 1) (4, 1) (5, 1) (6, 1) (6, 2) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   5 :
(2, 1) (3, 1) (4, 1) (5, 1) (6, 1) (6, 2) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径   6 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (6, 2) (7, 2) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   7 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (6, 2) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   8 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (6, 2) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径   9 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (6, 2) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  10 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  11 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  12 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  13 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  14 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  15 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  16 :
(2, 1) (3, 1) (4, 1) (5, 1) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  17 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (6, 2) (7, 2) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  18 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (6, 2) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  19 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (6, 2) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  20 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (6, 2) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  21 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  22 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  23 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  24 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  25 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  26 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  27 :
(2, 1) (3, 1) (4, 1) (4, 2) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  28 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  29 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  30 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  31 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  32 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  33 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  34 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  35 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (4, 4) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  36 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (4, 4) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  37 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (4, 4) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  38 :
(2, 1) (3, 1) (4, 1) (4, 2) (4, 3) (4, 4) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  39 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (6, 2) (7, 2) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  40 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (6, 2) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  41 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (6, 2) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  42 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (6, 2) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  43 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  44 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  45 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  46 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  47 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  48 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  49 :
(2, 1) (3, 1) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  50 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  51 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  52 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  53 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  54 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  55 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  56 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  57 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  58 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  59 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  60 :
(2, 1) (3, 1) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  61 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (6, 2) (7, 2) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  62 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (6, 2) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  63 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (6, 2) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  64 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (6, 2) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  65 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  66 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  67 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  68 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  69 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  70 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  71 :
(2, 1) (2, 2) (3, 2) (4, 2) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  72 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (6, 3) (7, 3) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  73 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (6, 3) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  74 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (6, 3) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  75 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  76 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  77 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  78 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (5, 3) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  79 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  80 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  81 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  82 :
(2, 1) (2, 2) (3, 2) (4, 2) (4, 3) (4, 4) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  83 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (4, 4) (5, 4) (6, 4) (7, 4) (7, 5) (7, 6) (7, 7)

最短路径  84 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (4, 4) (5, 4) (6, 4) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  85 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (4, 4) (5, 4) (5, 5) (6, 5) (7, 5) (7, 6) (7, 7)

最短路径  86 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (4, 4) (5, 4) (5, 5) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  87 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (3, 5) (3, 6) (4, 6) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  88 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (3, 5) (3, 6) (4, 6) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径  89 :
(2, 1) (2, 2) (2, 3) (2, 4) (3, 4) (3, 5) (3, 6) (3, 7) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径  90 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (3, 5) (3, 6) (4, 6) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  91 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (3, 5) (3, 6) (4, 6) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径  92 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (3, 5) (3, 6) (3, 7) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径  93 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (2, 6) (3, 6) (4, 6) (5, 6) (5, 7) (6, 7) (7, 7)

最短路径  94 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (2, 6) (3, 6) (4, 6) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径  95 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (2, 6) (3, 6) (3, 7) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径  96 :
(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (2, 6) (2, 7) (3, 7) (4, 7) (5, 7) (6, 7) (7, 7)

最短路径长度： 11

最短路径条数： 96

 

#include <iostream>#include <string>#include <cstdio>#include <cstring>#include <cstdlib>#include <queue>#include <stack>using namespace std;const int SIZE = 102;//边界数组,四个方向，按照下、右、上、左的顺序int coordinate[4][2] = {1,0, 0,1, -1,0, 0,-1};stack<int> sx;stack<int> sy;stack<int> sxCopy;stack<int> syCopy;int mazeBfs[SIZE][SIZE];  //广搜用的迷宫int mazeDfs[SIZE][SIZE];  //深搜用的迷宫int oddEven[SIZE][SIZE];  //奇偶剪枝状态数组int n;  //迷宫行数int m;  //迷宫列数int k;  //封闭房间数int kr, kl; //每个封闭房间的行号和列号int p, q;  //小鼠a的行号和列号int r, s;  //小鼠b的行号和列号int ShortestPathLength; //最短路径的长度int ShortestPahtNumber; //最短路径的条数int ans = 1; //输出第ans条最短路径//广搜求最短路径长度//int BFS(int p, int q, int r, int s, int len, int n, int m);int BFS();//深搜求最短路径条数//void DFS(int x, int y, int r, int s, int len, int n, int m, int shortlength);void DFS(int x, int y, int len);int main(){    while (scanf("%d%d%d", &n, &m, &k) != EOF)    {        memset(mazeBfs, 0, sizeof(mazeBfs));  //初始化迷宫        memset(mazeDfs, 0, sizeof(mazeDfs));        //奇偶剪枝数组初始化        for (int i=0; i<=n; i++)        {            if (i%2 == 1)            {               for (int j=0; j<=m; j++)               {                   if (j%2 == 1)                   {                       oddEven[i][j] = 1;                   }                   else                   {                       oddEven[i][j] = 0;                   }               }            }            else            {                for (int j=0; j<=m; j++)                {                    if (j%2 == 1)                    {                        oddEven[i][j] = 0;                    }                    else                    {                        oddEven[i][j] = 1;                    }                }            }        }        for (int i=1; i<=k; i++)        {            scanf("%d%d", &kr, &kl);  //输入封闭房间的坐标            //存入迷宫中，迷宫中，1代表封闭房间，0代表可以走            mazeBfs[kr][kl] = 1;            mazeDfs[kr][kl] = 1;        }        scanf("%d%d", &p, &q);  //小鼠a的坐标        scanf("%d%d", &r, &s);  //小鼠b的坐标        //求最短路径长度        ShortestPathLength = BFS();        if (ShortestPathLength == -1) //没路可走时        {            printf("No Solution!\n");            continue;        }        //求最短路径条数及输出所有的最短路径        ShortestPahtNumber = 0;        sx.push(p);        sy.push(q);        DFS(p, q, 0);        //输出结果        printf("最短路径长度： %d\n\n", ShortestPathLength);        printf("最短路径条数： %d\n\n", ShortestPahtNumber);    }    return 0;}int BFS(){    queue<int> qx;  //存横坐标的队列    queue<int> qy;  //存纵坐标的队列    queue<int> qlen;  //存长度的队列    int xa, ya; //当前节点坐标    int length; //到达当前节点长度    qx.push(p);    qy.push(q);    qlen.push(0);    mazeBfs[p][q] = 1;    while (!qx.empty())    {        if ((qx.front()==r) && (qy.front()==s)) //判断是否到达小鼠b        {            return qlen.front();        }        //临时保存队头值        int xx, yy ,ll;        xx = qx.front();        yy = qy.front();        ll = qlen.front();        //保存完之后，出队        qx.pop();        qy.pop();        qlen.pop();        for (int i=0; i<4; i++)        {            //算第i方向上的新值            xa = xx + coordinate[i][0];            ya = yy + coordinate[i][1];            length = ll;            //新的点在迷宫内，且没有走过            if ((xa>=1) && (xa<=n) && (ya>=1) && (ya<=m) && (mazeBfs[xa][ya]==0))            {                //入队                qx.push(xa);                qy.push(ya);                length += 1;                qlen.push(length);                //标记新点                mazeBfs[xa][ya] = 1;            }        }    }    return -1;  //如果没有路，返回0}void DFS(int x, int y, int len){    if ((x==r) && (y==s) && (len==ShortestPathLength))  //找到一条最短路径    {        ShortestPahtNumber++;        //输出最短路径        printf("最短路径 %3d :\n", ans++);        int j = sx.size();        for (int i=1; i<=j; i++)        {           sxCopy.push(sx.top());           sx.pop();           syCopy.push(sy.top());           sy.pop();        }        for (int i=1; i<=j; i++)        {            printf("(%d, %d) ", sxCopy.top(), syCopy.top());            sx.push(sxCopy.top());            sxCopy.pop();            sy.push(syCopy.top());            syCopy.pop();        }        printf("\n\n");        return ;    }    //一般剪枝    int theoryShortestLength; //当前节点到终点的理论最小值    theoryShortestLength = (abs(x-r)) + (abs(y-s));    if ((len+theoryShortestLength) > ShortestPathLength) //当前长度+理论最小值>最短路径长度    {        return ;    }    //奇偶剪枝    if ((ShortestPathLength-len)%2 != ((abs(oddEven[x][y]-oddEven[r][s])) % 2))    {        return ;    }    for (int i=0; i<4; i++)    {        int xx, yy;        xx = x + coordinate[i][0];        yy = y + coordinate[i][1];        if ((xx>=1) && (xx<=n) && (yy>=1) && (yy<=m) && (mazeDfs[xx][yy]==0))        {            sx.push(xx);            sy.push(yy);            mazeDfs[xx][yy] = 1;            DFS(xx, yy, len+1);            //回溯            sx.pop();            sy.pop();            mazeDfs[xx][yy] = 0;        }    }}