/*
	This script/program belongs to alphaguy4[Github]
*/
#include <iostream>
#include <iterator>
#include <utility>
#include <memory.h>
#include <queue>
#include <stack>
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <algorithm>
#include <set>
#include <map>
#include <vector>
#include <ctype.h>

#define si(i) scanf("%d",&i)
#define sll(i) scanf("%lld",&i)
#define ss scanf("\n%s",i)
#define ll long long
#define pb push_back
#define mp make_pair
#define fs first
#define sc second
#define pii pair<int,int>
#define pll pair<ll,ll>
#define REP(i,n) for(int i=0;i<n;i++)
#define FOR(i,j,n) for(int i=j;i<n;i++)
#define FORR(i,j,n) for(int i=n-1;i>-1;i--)
#define test(t) int t;si(t);while(t--)
#define M 1000000007
#define PI 3.141592653589793
#define sort(a) sort(a.begin(),a.end())
#define rev(a) reverse(a.begin(),a.end())
using namespace std;

typedef vector<int> vi;
typedef vector<pair<int,int> > vii;
typedef vector<pair<int,pair<int,int> > > viii;
typedef vector<pair<string,int> > vsi;
typedef set<int> si;
typedef map<int,int> mii;
typedef map<string,int> msi;
si s,s1;
mii m;
set<int> :: iterator it,jt;
void compress_and_insert(int n){
	int c=1;
	for(it = s1.begin();it != s1.end();it++){
		s.insert(c);
		m[*it] = c++;
	}
	
}
int main(){
	int n;
	test(t){
		si(n);
		vii v,c;
		v.clear();
		m.clear();
		s1.clear();
		int a,b;
		REP(i,n){
			si(a);
			si(b);
			v.pb(mp(a,b));
			s1.insert(a);
			s1.insert(b);
		}
		rev(v);
		compress_and_insert(n);
		int ans=0;
		s.insert(M);
		REP(i,n){
			int a = m[v[i].fs];
			int b = m[v[i].sc];
			//cout << a << " " << b << endl;
			it = s.lower_bound(a);
			jt = s.upper_bound(b);
			//cout << a << " " << *it << endl;
			//cout << b << " " << *jt << endl;
			if(it != jt){
				s.erase(it,jt);
				ans++;
			}
			//for(it = s.begin();it!=s.end();it++)
			//	cout << *it << " ";
			//cout << endl;
		}
		cout << ans << endl;
	}
	return 0;
}