#include<cstdio>
#include<cstring>
#include<set>
#include<algorithm>

using namespace std;

int s,br,z,sol,sol1,x,y,n,p[1000100],t[1000];



int main(){

	scanf("%d",&s);

	for(int k = 0;k < s; k++){

		sol = sol1 = 0;

		n = br = 0;

		scanf("%d",&z);

		for(int j = 0;j < z; j++){

			scanf("%d %d",&x ,&y);

			t[br] = x;

			br++;

			t[br] = y;

			br++;

			p[x] = 1;

			p[y] = -1;

		}

		sort(t,t + br);

		for(int i = 0;i <= z * 2 + 100;i++){

			sol1 = sol1 + p[t[i]];

			sol = max(sol1,sol);
		}

		printf("%d\n",sol);

		memset(p,0,sizeof p);

		memset(t,0,sizeof t);
	}

	return 0;
}