#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
bool sor_col(const vector<int> &v1, const vector<int> &v2){
    if(v1[0]>v2[0]) return true;
    if(v1[0]<v2[0]) return false;
    return v1[1]<v2[1];
}
 
int main(){
    int n,x,y;
    cin>>n;
    vector<vector<int>> v(n);
    for(int i=0;i<n;i++){
        cin>>x>>y;
        v[i].push_back(x);
        v[i].push_back(y);
    }
    sort(v.begin(),v.end(),sor_col);
    for (const auto& vec: v)
    {
    	for (const auto& integer: vec)
    		cout << integer << ' ';
    	cout << endl;
    }
    return 0;
}

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7
5 8
4 6
3 1
5 2
4 9
5 3
4 7