#include<bits/stdc++.h> using namespace std; int main(){ int a[19198][5],n,i; int v[19198]; cin>>n; for(i = 1;i <= n;i++){ cin>>a[i][1]>>a[i][2]; } for(i = 1;i <= n;i++){ v[i] = a[i][1] * 10 + a[i][2]; } sort(v,v + n + 1); for(i = 1;i <= n;i++){ cout<<v[i] / 10<<" "<<v[i] % 10<<endl; } }