hdu 4882 ZCC Loves Codefires（贪心）

# include<stdio.h>
# include <algorithm>
# include <string.h>
using namespace std;
struct node
{
int v;
int t;
};
struct node a[100010];
bool cmp(node a,node b)
{
return  a.v *a.t+(a.v+b.v)*b.t<b.v*b.t+(a.v+b.v)*a.t;
}
int main()
{
int n;
__int64 sum;
int i;
while(~scanf("%d",&n))
{

for(i=0;i<n;i++)
scanf("%d",&a[i].v);
for(i=0;i<n;i++)
scanf("%d",&a[i].t);
sort(a,a+n,cmp);
__int64 sum1=0;
sum=0;
for(i=0;i<n;i++)
{
sum = (a[i].v+sum);
sum1+=sum*a[i].t;
}
printf("%I64d\n",sum1);
}
return 0;
}