#include <stdio.h>
#include <malloc.h>
#define MaxSize 100
#define M 4
#define N 4
//以下定义邻接表类型
typedef struct ANode            //边的结点结构类型
{
    int i,j;                    //该边的终点位置(i,j)
    struct ANode *nextarc;      //指向下一条边的指针
} ArcNode;

typedef struct Vnode            //邻接表头结点的类型
{
    ArcNode *firstarc;          //指向第一条边
} VNode;

typedef struct
{
    VNode adjlist[M+2][N+2];    //邻接表头节点数组
} ALGraph;                      //图的邻接表类型

typedef struct
{
    int i;                      //当前方块的行号
    int j;                      //当前方块的列号
} Box;

typedef struct
{
    Box data[MaxSize];
    int length;                 //路径长度
} PathType;                     //定义路径类型

int visited[M+2][N+2]= {0};
int count=0;
void CreateList(ALGraph *&G,int mg[][N+2])
//建立迷宫数组对应的邻接表G
{
    int i,j,i1,j1,di;
    ArcNode *p;
    G=(ALGraph *)malloc(sizeof(ALGraph));
    for (i=0; i<M+2; i++)                   //给邻接表中所有头节点的指针域置初值
        for (j=0; j<N+2; j++)
            G->adjlist[i][j].firstarc=NULL;
    for (i=1; i<=M; i++)                    //检查mg中每个元素
        for (j=1; j<=N; j++)
            if (mg[i][j]==0)
            {
                di=0;
                while (di<4)
                {
                    switch(di)
                    {
                    case 0:
                        i1=i-1;
                        j1=j;
                        break;
                    case 1:
                        i1=i;
                        j1=j+1;
                        break;
                    case 2:
                        i1=i+1;
                        j1=j;
                        break;
                    case 3:
                        i1=i, j1=j-1;
                        break;
                    }
                    if (mg[i1][j1]==0)                          //(i1,j1)为可走方块
                    {
                        p=(ArcNode *)malloc(sizeof(ArcNode));   //创建一个节点*p
                        p->i=i1;
                        p->j=j1;
                        p->nextarc=G->adjlist[i][j].firstarc;   //将*p节点链到链表后
                        G->adjlist[i][j].firstarc=p;
                    }
                    di++;
                }
            }
}
//输出邻接表G
void DispAdj(ALGraph *G)
{
    int i,j;
    ArcNode *p;
    for (i=0; i<M+2; i++)
        for (j=0; j<N+2; j++)
        {
            printf("  [%d,%d]: ",i,j);
            p=G->adjlist[i][j].firstarc;
            while (p!=NULL)
            {
                printf("(%d,%d)  ",p->i,p->j);
                p=p->nextarc;
            }
            printf("\n");
        }
}
void FindPath(ALGraph *G,int xi,int yi,int xe,int ye,PathType path)
{
    ArcNode *p;
    visited[xi][yi]=1;                   //置已访问标记
    path.data[path.length].i=xi;
    path.data[path.length].j=yi;
    path.length++;
    if (xi==xe && yi==ye)
    {
        printf("  迷宫路径%d: ",++count);
        for (int k=0; k<path.length; k++)
            printf("(%d,%d) ",path.data[k].i,path.data[k].j);
        printf("\n");
    }
    p=G->adjlist[xi][yi].firstarc;  //p指向顶点v的第一条边顶点
    while (p!=NULL)
    {
        if (visited[p->i][p->j]==0) //若(p->i,p->j)方块未访问,递归访问它
            FindPath(G,p->i,p->j,xe,ye,path);
        p=p->nextarc;               //p指向顶点v的下一条边顶点
    }
    visited[xi][yi]=0;
}

int main()
{
    ALGraph *G;
    int mg[M+2][N+2]=                           //迷宫数组
    {
        {1,1,1,1,1,1},
        {1,0,0,0,1,1},
        {1,0,1,0,0,1},
        {1,0,0,0,1,1},
        {1,1,0,0,0,1},
        {1,1,1,1,1,1}
    };
    CreateList(G,mg);
    printf("迷宫对应的邻接表:\n");
    DispAdj(G); //输出邻接表
    PathType path;
    path.length=0;
    printf("所有的迷宫路径:\n");
    FindPath(G,1,1,M,N,path);
    return 0;
}