哪里有问题请帮我找一下，找了一上午，最后直接折了

//搜索dfs 走迷宫
#include <iostream>
#include <cstdio>
using namespace std;
int m,n;//有 m 行、n 列
short a[20][20];    //迷宫
bool b[20][20] = {0},found = false;
int ans[1000][2];
short x[4] = {-1,0,1,0},y[4] = {0,1,0,-1};      //左上右下 优先顺序
short start_x,start_y,end_x,end_y;  //最后两行是起始点和结束点
void print(int len);
void search(int p,int q,int k);    //初始坐标(p,q),当前路径长度k
int main()
{
    cin >> m >> n;
    for (int i=0;i<m;i++)
        for (int j=0;j<n;j++)
                cin >> a[i][j];
    cin >>  start_x >> start_y >> end_x >> end_y;
    b[start_x][start_y] = 1;
    search(start_x,start_y,0);  //起点等着直接输出'
    if (found == false)
    {
        cout << -1  ;
        return 0;
    }
    return 0;
}
void search(int p,int q,int k)
{
    for (int i=0;i<4;i++)
    {
        int xx = p + x[i];
        int yy = q + y[i];
        if (!b[xx][yy] && xx >=0 && xx<m && yy>=0 && yy<n && a[xx][yy] == 1)        //可以走，不越界，没走过
        {
            b[xx][yy] = 1;
            ans[k][0] = xx;         //没办法，先不存储起点了,但是，按照这里的写法，终点应该 会 被 存
            ans[k][1] = yy;
            if (xx == end_x && yy == end_y)
            {
                print(k);
                found = true;
            }
            else search(xx,yy,k+1);
            b[xx][yy] = 0;      //回溯 backtracking
        }
    }
}
void print(int len)
{

    cout << "(" << start_x <<"," << start_y << ")" ;       //每一次，都先输出起点
    for (int i=0;i<=len;i++)    
    {
        printf("->(%d,%d)",ans[i][0],ans[i][1]);
    }
    cout << endl;
}