TJU Vacation

Z is planning to visit the Tourist Kingdom for M days. This kingdom is full of lovely cities. During his stay Z would like to visit as many different cities as possible. He cannot visit more than one city on the same day.

Additionally,different cities may require him to stay for a different number of days.For each i,city i counts as visited if Z spends at least d[i] days in the city.

Help Z find the maximal number of cities he can visit during his vacation.

Input

First a integer T,the number of test cases.For each test case,the first line is M and N,the total days Z has and the number of cities.(M,N≤50)

Then N integers,meaning the int[] d.

Output

The maximal number of cities Z can visit.

Sample Input

3
5 3
2 2 2
5 3
5 6 1
6 5
1 1 1 1 1

Sample Output

2
1
5

题目概述：简单地说就是用最少的天数游览最多的城市，需要注意的是 并不是到过每个城市就算游览过，而是 需要在不同的城市停留不同的天数，满足条件时才算游览过。

解题思路：本体解题方法比较简单，用  贪心的思想  就能轻易得出答案。

源代码：

#include<iostream>
#include<set>
using namespace std;
int main()
{
    multiset<int>Set;    //定义一个set 
    int T,M,N;
    cin>>T;
    while(T--)
    {
         int max=0,temp;
         cin>>M>>N;
         for(int i=0;i<N;++i)   //输入需要在每个城市停留的天数 
         {
             cin>>temp;
             Set.insert(temp);
         }
         multiset<int>::iterator pos;   //迭代器 
         for(pos=Set.begin();pos!=Set.end();++pos)
         {
             if(M-*pos>=0){++max;M-=*pos;}  //贪心法求得答案 
             else break;
         }
         Set.clear();                   //清空set，否则会影响下一次的结果 
         cout<<max<<endl;
    }
    return 0;
}