Codeforces Round ＃643 (Div. 2)——B. Young Explorers

Topic link ：https://codeforces.com/problemset/problem/1355/B
Title Description ： Enter the explorer's experience level , When forming a team, the number of people in a team cannot be less than the experience level of any person in the team （ The number of people is greater than the highest experience level in the team ）, It is required to form the largest number of teams .
Their thinking ： greedy Choose people with low experience level to form a team that meets the conditions first .—— First sort by experience level from low to high , When the conditions are met, form a team .
Code ：

#include<iostream>
#include<algorithm>
using namespace std;
int num[200005];
int main()
{
    
	int t;
	cin >> t;
	while (t--)
	{
    
		int n;
		cin >> n;
		for (int i = 0; i < n; i++)
			cin >> num[i];
		sort(num, num + n);
		int ans = 0, count = 0;
		for (int i = 0; i < n; i++)
		{
    
			count++;
			if (count >= num[i])
			{
    
				ans++;
				count = 0;
			}
		}
		cout << ans << endl;
	}
	return 0;
}