牛客网PAT练兵场-月饼

题解：用struct排序月饼的平均价格，一直取最大

题目地址：https://www.nowcoder.com/questionTerminal/6fc9a928c7654b0fbc37d16b8bd29ff9

 /**
 *
 *作者:Ycute
 *时间:2019-11-01-14.30.12
 *题目简单描述:struct排序
 */

 #include<iostream>
 #include<cmath>
 #include<cstring>
 #include<algorithm>
 #include<vector>
 using namespace std;
 struct shop{
     int num;
     int price;
     double pva;
 };

 bool cmp(struct shop a,struct shop b){
     return a.pva>b.pva;
 }

 int main(){
     struct shop s[];
     int t,nnum;
     scanf("%d %d",&t,&nnum);
     for(int i=;i<t;i++){
         scanf("%d",&s[i].num);
     }
     for(int i=;i<t;i++){
         scanf("%d",&s[i].price);
         s[i].pva=s[i].price*1.0/s[i].num;
     }
     sort(s,s+t,cmp);
     int i=;
     double sum=;
     while(nnum){
         if(s[i].num<=nnum){//充足情况
             sum+=s[i].price;
             nnum-=s[i++].num;
             //cout<<i<<" "<<sum<<endl;
         }else{
             sum+=(s[i].price*1.0/s[i].num)*nnum;
             break;
         }
     }
     printf("%.2lf\n",sum);
     return ;
 }