Question

c语言我的程序编译错误是为什么？

#include<algorithm>
#include<cstdio>
#include<stdlib.h>
#include<iostream>
struct node
{
double p;
double va;
double ave;
}food[1000+20];
bool cmp(node a,node b)
{
return a.ave>b.ave;
}
using namespace std;
int main()
{
double v,n;double sum;
while(cin>>v>>n)
{ sum=0;
if(v==-1&&n==-1)
break;
for(int i=0;i<n;i++)
{
cin>>food[i].p>>food[i].va;
food[i].ave=food[i].p/food[i].va;
}
sort(food,food+n,cmp);
for(int j=0;j<n&&v!=0;j++)
{
if(v>=food[j].va)
{
sum+=food[j].p;
v-=food[j].va;
}
else
{
sum+=food[j].p/food[j].va*v;
v=0;
}
}
printf("%.3lf\n",sum);
}
return 0;
}

Answer 1

int main()
{
    int n; //改为整型，编译通过，不知道你的代码想实现什么？
    double v, sum;
    while(cin>>v>>n)
    {
        sum=0;
        if(v==-1&&n==-1)
            break;
        for(int i=0;i<n;i++)
        {
            cin>>food[i].p>>food[i].va;
            food[i].ave=food[i].p/food[i].va;
        }
        sort(food,food+n,cmp);
        for(int j=0;j<n&&v!=0;j++)
        {
            if(v>=food[j].va)
            {
                sum+=food[j].p;
                v-=food[j].va;
            }
            else
            {
                sum+=food[j].p/food[j].va*v;
                v=0;
            }
        }
        printf("%.3lf\n",sum);
    }
    return 0;
}

Answer 2

这是cpp好吗