1，2AC，后面全RE！！！为什么？？？

#include <iostream>
#include <cmath>
#include <algorithm>
using namespace std;

struct ll
{
    int x;
    int y;
    int t;
}ys[50005];

struct lll
{
    int x[315];
    int y[315];
    int sum = 0;
}qz[315];

int map[315][315] = { 0 }, n, fx[4] = { -1,1,0,0 }, fy[4] = { 0,0,-1,1 },
x, y, xl, yl, in, ans = 999;

void BFS(int k)
{
    if (qz[k].sum == 0)return;
    if (ys[in].t == -1)return;
    for (int i = 1; i <= qz[k].sum; i++)
    {
        x = qz[k].x[i];
        y = qz[k].y[i];
        if (map[x][y] == -1)continue;
        for (int j = 0; j < 4; j++)
        {
            xl = x + fx[j];
            yl = y + fy[j];
            if (xl < 0)continue;
            if (yl < 0)continue;
            if (map[xl][yl] == 0)
            {
                map[xl][yl] = k + 1;
                qz[k + 1].sum++;
                qz[k + 1].x[qz[k+1].sum] = xl;
                qz[k + 1].y[qz[k + 1].sum] = yl;
            }
        }
    }
    if (ys[in].t == k + 1)
    {
        while (ys[in].t == k + 1)
        {
            x = ys[in].x;
            y = ys[in].y;
            map[x][y] = -1;
            for (int j = 0; j < 4; j++)
            {
                xl = x + fx[j];
                yl = y + fy[j];
                if (xl < 0)continue;
                if (yl < 0)continue;
                map[xl][yl] = -1;
            }
            in++;
        }
    }
    BFS(k + 1);
}

int main()
{
    int max = 0;
    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        cin >> ys[i].x >> ys[i].y >> ys[i].t;
        if (ys[i].t > max)max = ys[i].t;
    }
    ys[n + 1].t = -1;
    qz[0].x[1] = 0;
    qz[0].y[1] = 0;
    qz[0].sum = 1;
    map[0][0] = 999;
    in = 1;
    BFS(0);
    for (int i = 0; i <= max; i++)
    {
        for (int j = 0; j <= max; j++)
        {
            if (map[i][j] <= 0)continue;
            if (map[i][j] < ans)ans = map[i][j];
        }
    }
    if (map[0][0] == 999)ans = 0;
    if (ans == 999)ans = -1;
    cout << ans << endl;
    return 0;
}