#include<iostream>
#include <algorithm>
using std::endl;
using std::cin;
using std::cout;
using std::sort;
const int MAXN = 5000 + 200;
struct stick{
	int length;
	int weight;
	//标记是否访问过
	int tag;
}sticks[MAXN];
//排序函数
bool cmp(stick a , stick b)
{
	if(a.length > b.length)
		return true;
	if(a.length == b.length)
		return a.weight > b.weight;
	return false;
}
int main()
{
#ifdef LOCAL
	freopen("input.txt" , "r" , stdin);
#endif
	int T;
	cin >> T;
	while(T--)
	{
		int n;
		cin >> n;
		for(int i=0; i<n; ++i)
		{
			cin >> sticks[i].length >> sticks[i].weight;
			sticks[i].tag = 0;
		}
		sort(sticks , sticks+n , cmp);
		int time = 0 , weight;
		for(int i=0; i<n; ++i)
		{
			//对每个未访问过的stick进行遍历
			if(!sticks[i].tag)
			{
				sticks[i].tag = 1;
				time++;
				weight = sticks[i].weight;
				for(int j=i+1; j<n; ++j)
				{
					if(!sticks[j].tag && weight >= sticks[j].weight)
					{
						//如果符合条件可以减免然后更新下次比较的重量
						weight = sticks[j].weight;
						//更新访问标记
						sticks[j].tag = 1;
					}
				}
			}
		}
		cout << time << endl;
	}
	return 0;
}