#include <bits/stdc++.h>
using namespace std;

struct treasure{   //连锁数据排序
    double m, v, rate;
};

bool cmp(treasure a, treasure b)
{
    return a.rate>b.rate;
}

int main()
{
    int N, T;
    cin >> N >> T;
    vector<treasure> treasures(N);
    double sum=0;
    for(int i=0; i<N; i++)
    {
        cin >> treasures[i].m >> treasures[i].v;
        treasures[i].rate=treasures[i].v/treasures[i].m;
    }
    sort(treasures.begin(), treasures.end(), cmp);
    for(int i=0; i<N; i++)
    {
        if(T>=treasures[i].m)   //尽量不造成出现负数的情况
        {
            T-=treasures[i].m;
            sum+=treasures[i].v;
        }
        else
        {
            sum+=treasures[i].rate*T;
            T=0;
            break;
        }
    }
    printf("%.2lf", sum);
    return 0;
}

#include<iostream> #include<vector> #include<algorithm> #include<iomanip> using namespace std; struct gold { double value; double weight; double rate; }; bool cmp(const gold& t1,const gold& t2) { return t1.rate > t2.rate; } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n, t; double numt = 0; double numv=0; vector<gold> v; cin >> n >> t; if (n < 0 || t < 0 || n>100 || t>1000)return 0; v.resize(n); for (int i = 0; i < n; i++) { cin >> v[i].weight >> v[i].value; if (v[i].value < 1 || v[i].weight < 1 || v[i].value>120)return 0; v[i].rate = v[i].value / v[i].weight; } sort(v.begin(),v.end(),cmp); int i = 0; while (numt <= t && i < n) { numt += v[i].weight;//可能会大于 numv += v[i].value; i++; } if (numt > t) { numv-=(numt - t)* v[i-1].rate; } cout << fixed<<setprecision(2)<<numv; return 0; }

#include<iostream>
#include<string>
#include<cmath>
#include<algorithm>
#include<cstdio>
using namespace std;
const int N=102;
int n,zhilian;
struct gold{
	double weight;
	double worth;
	double every;
}go[N];
bool compair(gold a,gold b){
	return a.every>b.every;
}
int main(){
	cin>>n>>zhilian;
	int i=0;
	int t=n;
	while(t--){
		int x1,x2;
		scanf("%d%d",&x1,&x2);
		go[i].weight=x1,go[i].worth=x2;
		go[i].every=(double)x2/x1;
		i++;	
	}
	sort(go,go+n,compair);
	double res=0;
	for(int j=0;j<n;j++){
		if(zhilian>go[j].weight) res+=go[j].worth,zhilian-=go[j].weight;
		else {
			res+=go[j].every*zhilian;
			break;
		}
	}
	printf("%.2lf",res);
	return 0;
	
}

/上天啊 难道你看不出我很爱她/ #include<bits/stdc++.h> using namespace std; struct Node{ double m,v; double avg; }a[110]; bool cmp(Node x,Node y) { return x.avg>y.avg; } int main() { int n,t;cin>>n>>t; for(int i = 1;i<=n;i++) { cin>>a[i].m>>a[i].v; a[i].avg = a[i].v/a[i].m; } sort(a+1,a+1+n,cmp); double sum = 0; for(int i = 1;i<=n;i++) { if(t>=a[i].m) { sum = sum+a[i].v; t = t-a[i].m; } else { sum = sum+t1.0a[i].avg; break; } } cout<<fixed<<setprecision(2)<<sum; }