#include <bits/stdc++.h>

using namespace std;
ifstream fin("infasuratoare.in");
ofstream fout("infasuratoare.out");
int n,i;
struct number
{
    double x,y;
}v[120005];
void read()
{
    fin>>n;
    for(i=1;i<=n;i++)
        fin>>v[i].x>>v[i].y;
}
double comp(number a,number b)
{
    return ((a.x<b.x)||(a.x==b.x&&a.y<b.y));
}
void sortare()
{
    sort(v+1,v+n+1,comp);
    for(i=1;i<=n;i++)
        fout<<setprecision(9)<<(double)v[i].x<<" "<<setprecision(9)<<v[i].y<<'\n';
}
int main()
{
    read();
    sortare();
    return 0;
}