UVa1149 - Bin Packing

//UVa1149 - Bin Packing
//贪心，背包，乘船问题
#include<iostream>
#include<algorithm>
using namespace std;
int a[101000];	//bag
int main(){
	//freopen("UVa1149.in","r",stdin);
	int t,n,m;
	cin>>t;
	while(t--){
		cin>>n>>m;
		for(int i=0;i<n;i++) cin>>a[i];
		sort(a,a+n);
		int left=0, right=n-1, ans = 0;
		while(left <= right){
			if(a[right]+a[left] > m) --right;
			else --right, ++left;
			++ans;
		}
		cout<<ans<<"\n";
		if(t)cout<<"\n";
	}
	return 0;
}
//已AC