#include<iostream>
#include<algorithm>
using namespace std;
 
bool sort_sec(pair<int,int> a,pair<int,int> b)
{
	return a.second<b.second;
}
 
int main() {
	int m;
	cin>>m;
	while(m>0)
	{
		int n,c=1;
		cin>>n;
		pair<int,int> p[n];
		for(int i=0;i<n;i++)
			cin>>p[i].first>>p[i].second;
		sort(p,p+n,sort_sec);
        int j=0;
		for(int i=1;i<n;i++)
		{
			if(p[i].first >= p[j].second){
                j=i;
            	c++;
            }
		}
		cout<<c<<endl;
		m--;
	}
	return 0;
}
 
//  output:
// 1
// 2
// 3

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

MwozCjMgOQoyIDgKNiA5CjQKMSA3CjUgOAo3IDgKMSA4CjYKNyA5CjAgMTAKNCA1CjggOQo0IDEwCjUgNw==

3
3
3 9
2 8
6 9
4
1 7
5 8
7 8
1 8
6
7 9
0 10
4 5
8 9
4 10
5 7