10分，求调，必关

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int m, n;
    cin>>m>>n;
    int x,y; 
    cin>>x>>y;
    if (x!=0&&y!=0) 
    {
        cout<<x<<" "<<y<<endl;
    } else 
    {
        return 0;
    }
    int total= m*n;
    for (int i=2;i<=total;i++) 
    {
        cin>>x>>y;
        if (x==0||y==0) 
        {
            break;
        }
        cout<<x<<" "<<y<<endl;
    }
    return 0;
}