#include<bits/stdc++.h> using namespace std; int n; struct point { int a; int b; }; point a[100010]; bool cmp(point x,point y) { if(x.a!=y.a) { return x.a<y.a; } return x.b<y.b; } int main() { cin>>n; for(int i=1;i<=n;i++) { cin>>a[i].a; cin>>a[i].b; } sort(a+1,a+n+1,cmp); for(int i=1;i<=n;i++) { cout<<a[i].a; cout<<" "; cout<<a[i].b; cout<<endl; } return 0; }