#include <stdio.h> #include <stdlib.h> #include <string.h> #define LEN 500 typedef struct MazeRoute { char direction[500]; int top; }MazeRoute; int isRouted=0; void travelMaze(int map[230][230],MazeRoute *s,int x,int y,int n, int k) { int i; if(x==n&&y==k-1) { for(i=0;i<s->top;i++) printf("%c",s->direction[i]); isRouted=1; return; } map[x][y]=-1; if(map[x][y+1]==0){ s->direction[s->top++] = 'R'; travelMaze(map,s,x,y+1,n,k); s->top--; } if(map[x+1][y]==0){ s->direction[s->top++] = 'D'; travelMaze(map,s,x+1,y,n,k); s->top--; } if(map[x][y-1]==0){ s->direction[s->top++] = 'L'; travelMaze(map,s,x,y-1,n,k); s->top--; } if(map[x-1][y]==0){ s->direction[s->top++] = 'U'; travelMaze(map,s,x-1,y,n,k); s->top--; } return; } int main() { int n=0,k=0; int i,j=0; MazeRoute *s; char str[LEN]; int len; int x=1,y=1; int map[230][230]={0}; while(1) { gets(str); if(strlen(str)==0) break; len=strlen(str); for(i=1;i<len+1;i++) map[n+1][i]=str[i-1]-'0'; n++; } for(k=0;k<=n+1;k++) { for(j=0;j<=len+1;j++) { if(k==0||k==n+1||j==0||j==len+1) map[k][j]=1; } } s=(MazeRoute *)malloc(sizeof(MazeRoute)); if(s==NULL) { printf("malloc failed\n"); return 0; } s->top=0; travelMaze(map,s,x,y,n,i); if(!isRouted) printf("no pass"); printf("\n"); return 0; }请为这个代码标上注释

好的，以下是带有注释的代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define LEN 500

// 定义迷宫路径结构体
typedef struct MazeRoute {
    char direction[500]; // 记录路径
    int top; // 栈顶指针
} MazeRoute;

int isRouted=0; // 是否找到路径

// DFS 遍历迷宫
void travelMaze(int map[230][230], MazeRoute *s, int x, int y, int n, int k) {
    int i;

    // 如果到达终点，输出路径并结束递归
    if (x == n && y == k - 1) {
        for (i = 0; i < s->top; i++) {
            printf("%c", s->direction[i]);
        }
        isRouted = 1;
        return;
    }

    // 标记当前位置已访问
    map[x][y] = -1;

    // 向右探索
    if (map[x][y+1] == 0) {
        s->direction[s->top++] = 'R'; // 记录路径
        travelMaze(map, s, x, y + 1, n, k);
        s->top--; // 回溯，弹出栈顶元素
    }

    // 向下探索
    if (map[x+1][y] == 0) {
        s->direction[s->top++] = 'D';
        travelMaze(map, s, x + 1, y, n, k);
        s->top--;
    }

    // 向左探索
    if (map[x][y-1] == 0) {
        s->direction[s->top++] = 'L';
        travelMaze(map, s, x, y - 1, n, k);
        s->top--;
    }

    // 向上探索
    if (map[x-1][y] == 0) {
        s->direction[s->top++] = 'U';
        travelMaze(map, s, x - 1, y, n, k);
        s->top--;
    }

    return;
}

int main() {
    int n=0,k=0;
    int i,j=0;
    MazeRoute *s; // 定义迷宫路径结构体指针

    char str[LEN];
    int len;
    int x=1,y=1;
    int map[230][230]={0};

    // 读入迷宫地图
    while (1) {
        gets(str);

        if (strlen(str) == 0) {
            break;
        }

        len = strlen(str);
        for (i = 1; i < len + 1; i++) {
            map[n+1][i] = str[i-1] - '0';
        }
        n++;
    }

    // 将地图四周置为障碍
    for (k = 0; k <= n + 1; k++) {
        for (j = 0; j <= len + 1; j++) {
            if (k == 0 || k == n + 1 || j == 0 || j == len + 1) {
                map[k][j] = 1;
            }
        }
    }

    // 初始化迷宫路径结构体
    s = (MazeRoute*)malloc(sizeof(MazeRoute));
    if (s == NULL) {
        printf("malloc failed\n");
        return 0;
    }
    s->top = 0;

    // 遍历迷宫
    travelMaze(map, s, x, y, n, i);

    // 如果找不到路径，输出 "no pass"
    if (!isRouted) {
        printf("no pass");
    }
    printf("\n");

    return 0;
}