1 #include <iostream>
 2 #include <algorithm>
 3 
 4 using namespace std;
 5 
 6 struct Goods {                    //货物结构体（库存，总售价，单价）
 7     float mass, price, arg;
 8 }goods[1000];
 9 
10 bool cmp(Goods g1, Goods g2) {    //sort函数中返回bool的比较函数
11     return g1.arg > g2.arg;
12 }
13 
14 int main() {
15     int n = 0, d = 0;
16     float max = 0.0;
17     cin >> n >> d;                
18     for (int i = 0; i < n; i++) 
19         cin >> goods[i].mass;
20     for (int i = 0; i < n; i++) {
21         cin >> goods[i].price;
22         goods[i].arg = goods[i].price / goods[i].mass; //单价计算
23     }
24     sort(goods, goods+n,cmp);        //利用sort函数，按单价从大到小排序
25     for (int i = 0; i < n; i++) {
26         if (d >= goods[i].mass) {    //判断是否超过最大需求量
27             d -= goods[i].mass;        //d剩余部分
28             max += goods[i].price;
29         }
30         else {
31             max += goods[i].arg * d;    //临界部分，由d剩余部分*单价计算得出
32             break;
33         }
34     }
35     printf("%.2f", max);
36     return 0;
37 }