#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define rep(n) for (ll i=0;i<n;i++)
#define test ll t;cin>>t;while(t–)
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define mod 1000000007
#include
#include
#include
#include
#include
bool comparator (pair<int , int > a , pair<int, int > b) {
if ( a.second <= b.second) {
return true ;
}
return false ;
}
void solve()
{
int N ;
// No of activities
cin >> N ;
pair<int , int> arr[N];
for ( int i = 0 ; i < N ; i++) {
int x1, x2;
cin >> x1 >> x2;
arr[i] = make_pair(x1, x2);
}
sort (arr, arr + N, comparator);
for (int i = 0 ; i < N; i++) {
cout << arr[i].first << " " << arr[i].second << endl;
}
int count = 0, currentEnd = 0;
for (int i = 0; i < N ; i++) {
if (currentEnd > arr[i].first) {
continue;
}
else {
count++;
currentEnd = arr[i].second;
}
}
cout << count;
}
int main()
{
// fast
// #ifndef ONLINE_JUDGE
// freopen(“input.txt”, “r”, stdin);
// freopen(“output.txt” , “w” , stdout);
// #endif
ll t ;
cin >> t ;
while (t--) {
solve();
}
}