P2240求调（悬两关） 代码如下

#include<bits/stdc++.h>
using namespace std;
struct value
{
	int m;
	int v;
	double val;
}a[105];
bool cmp(value a,value b)
{
	return a.val>=b.val;
}
int sum,sum1;
int main(){
	int n,t;
	cin>>n>>t;
	for(int i=1;i<=n;i++)
	{
		cin>>a[i].m>>a[i].v;
		a[i].val=1.0*a[i].v/a[i].m;
	}
	sort(a+1,a+1+n,cmp);
	for(int i=1;i<=n;i++)
	{
		if(a[i].m<=t)
		{
			sum1+=a[i].v;
			t-=a[i].m;
		}
		else
		{
			sum1+=1.0*a[i].val*t;
			break;
		}
	}
	cout<<fixed<<setprecision(2);
	cout<<1.0*sum1;
	return 0;
}