为何运行出错？大家可以帮我一下吗？谢谢

#include<iostream> 
#include<vector>
using namespace std;

int main()
{
    int m, n;
    cin >> m >> n;
    vector<vector<int> > arr(n);
    for (int i = 0; i < n; i++)
    {
        int k;
        while (cin >> k)
        {
            arr[i].push_back(k);
            if (cin.get() == '\n')
                break;
        }
    }
    for (int j = 0; j < n; j++)
    {
        if (arr[j][0] == 2)
        {
            for (int k = 0; k < n; k++)
            {
                if (arr[k][1] == arr[j][1] && arr[k][2] == arr[j][2] && arr[k][0] == 1)
                    cout << arr[k][3]<<endl;
            }
        }
    }
}