#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pi acos(-1)

void sortLU(ll a[],ll n,ll b[])
{
    //to sort lower to upper
    ll i,j;
    for(i=0; i<n; i++)
    {
        for(j=0; j<n; j++)
        {
            if(a[i]<a[j]|| (a[i]==a[j] && b[i]>b[j]))
            {
                swap(a[i],a[j]);
                swap(b[i],b[j]);
            }
        }
    }
}

int main()
{
    int test;
    cin>>test;
    while(test--)
    {
        ll n;
        cin>>n;
        ll a[n],b[n];
        for(ll i=0; i<n; i++)
        {
            cin>>a[i]>>b[i];
        }
        sortLU(a,n,b);
        for(ll i=0; i<n; i++)
        {
            cout<<a[i]<<" "<<b[i]<<endl<<endl;
        }
    }
    return 0;
}