调试显示Segmentation Fault，提交却过了，求调

#include<bits/stdc++.h>
using namespace std;


int n, m ,q;
int a[1010][1010], b[1010][1010];

void insert(int x1, int y1, int x2, int y2, int c)
{
    b[x1][y1] += c;
    b[x2 + 1][y1] -= c;
    b[x1][y2 + 1] -= c;
    b[x2 + 1][y2 + 1] += c;
}

int main()
{
    cin >> n >> m >> q;
    for(int i = 1;i <= n;i++)
    {
        for(int j = 1;j <= m;j++)
        {
            cin >> a[i][j];
        }
    }
    for(int i = 1;i <= n;i++)
    {
        for(int j = 1;j <= m;j++)
        {
            insert(i, j, i, j, a[i][j]);
        }
    }
    for(int i = 1;i <= q;i++)
    {
        int x1, y1, x2, y2, c;
        cin >> x1 >> y1 >> x2 >> y2 >> c;
        insert(x1, y1, x2, y2, c);
    }
    for(int i = 1;i <= n;i++)
    {
        for(int j = 1;j <= m;j++)
        {
            b[i][j] = b[i - 1][j] + b[i][j - 1] - b[i - 1][j - 1] + b[i][j];
        }
    }
    for(int i = 1;i <= n;i++)
    {
        for(int j = 1;j <= m;j++)
        {
           cout << b[i][j] << " ";
        }
        cout << endl;
    }
    return 0;
}

提问于6天前

y总的小迷弟cxr

954