不是固定点RE 每次测评会在不同的点RE 有时还会显示编译失败 有没有大佬可以麻烦解答一下呢

#include <iostream>
#include <queue>
#include <cstring>
#include <cstdio>
using namespace std;
const int N = 1005;
bool vis[N][N];
int n,times;
struct point
{
    int x,y;
};
int dx[4] = {1,-1,0,0};
int dy[4] = {0,0,1,-1};

void ini()
{
    memset(vis,1,sizeof(vis));
    for(int i = 1;i<=n;i++)
        for(int j = 1;j<=n;j++)
            vis[i][j] = 0;
    times = 0;
    // for(int i =0;i<=n+1;i++)
    // {
    //     for(int j = 0;j<=n+1;j++)
    //     {
    //         printf("vis[%d,%d] = %d\n",i,j,(int)vis[i][j]);
    //     }
    //     cout<<endl;
    // }
    
}
void input()
{
    cin>>n;
}
void check()
{
    if(times < 2*n-2)
    {
        int a,b;
        cin>>a>>b;
        vis[a][b] = 1;
        times++;
    }
}
void bfs()
{
    bool ans = 0;
    queue <point> q;
    q.push({1,1});
    while(!q.empty())
    {
        
        point now = q.front();
        point to;
        //printf("now : %d,%d\n",now.x,now.y);
        q.pop();
        if(now.x == n && now.y == n)
        {
            ans = 1;
            break;
        } 
        for(int i =0;i<4;i++)
        {
            to.x = now.x+dx[i];
            to.y = now.y+dy[i];
            if(!vis[to.x][to.y])
            {
                //printf("push:{%d,%d}\n",to.x,to.y);
                q.push(to);
                vis[to.x][to.y] = 1;
            }
        }
        if(now.x == 1 && now.y == 1) continue;
        check();
    }
    cout<<(ans ? "Yes" : "No")<<endl;
}
void work()
{
    input();
    ini();
    bfs();
}
int main()
{
    int t;
    cin>>t;
    while(t--) work();
    return 0;
}