#include 
     
      #include 
      
       #include 
       
        using namespace std;//思路： 用结构体存储月饼  里面存储 月饼的数量 价格 和单价//将月饼的单价进行排序//根据月饼的需求 依次卖出价格从高到低的月饼//终止条件为 某种月饼的数量大于还需要的月饼的数量 这时候 sum += 所需数量月饼 / 该种月饼的数量 * 该种月饼的价格struct node{    double quantity;    double price;    double perprice;};bool cmp(struct node a, struct node b){    return a.perprice > b.perprice;}int main() {    int kind;    double need;    cin >> kind >> need;    vector
        
          mooncake(kind);    for (int i = 0; i < kind; i++) {        cin >> mooncake[i].quantity;    }    for (int i = 0; i < kind; i++) {        cin >> mooncake[i].price;        mooncake[i].perprice = mooncake[i].price / mooncake[i].quantity;    }    sort(mooncake.begin(), mooncake.end(), cmp);    double Price = 0;    for (int i = 0; i < kind; i++) {        if (need > mooncake[i].quantity) {            need -=  mooncake[i].quantity;            Price += mooncake[i].price;        }else{            Price += mooncake[i].price * need / mooncake[i].quantity;            break;        }    }    printf("%.2lf\n", Price);    return 0;}