#include <bits/stdc++.h>
using namespace std;
int main()
{
int n;
while (cin >> n){
int x[n], y[n];
for (int i=0; i<n; i++){
cin >> x[i] >> y[i];
}
for (int j=0; j<n; j++){
for (int k=j+1; k<n; k++){
if (x[j]>x[k]||x[j]==x[k]&&y[j]>y[k]){
int temp1 = x[j];
x[j] = x[k];
x[k] = temp1;
int temp2 = y[j];
y[j] = y[k];
y[k] = temp2;
}
}
}
for (int l=0; l<n; l++){
cout << x[l] << " " << y[l] << endl;
}
}
return 0;
}