백준(BOJ) 1946 신입사원 *

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <math.h>
#include <queue>
#include <set>
#include <list>
#include <utility>
#include <functional>
#define MAX 2005
#define INF 987654321
#define MOD 1000000
#pragma warning(disable:4996)
using namespace std;
typedef long long ll;
typedef pair<int, int> pi;

int T, n, a, b;
vector<pi> v;

int main()
{
	scanf("%d", &T);
	for (int i = 0; i < T; i++)
	{
		v.clear();
		scanf("%d", &n);
		for (int k = 0; k < n; k++)
		{
			scanf("%d%d", &a, &b);
			v.push_back(make_pair(a, b));
		}
		sort(v.begin(), v.end());
		int cur = 1, a = v[0].first, b = v[0].second;
		for (int k = 1; k < v.size(); k++)
			if (v[k].second < b)
			{
				b = v[k].second;
				cur++;
			}
		printf("%d\n", cur);
	}
	return 0;
}