hdu 2090 算菜价

代码：

#include<cstdio>#include<cmath>using namespace std;int main(){    char str[100];    double p,q;    double ans=0;    while(~scanf("%s%lf%lf",str,&p,&q))    {        ans=ans+p*q;    }    printf("%.1lf\n",ans);//自动会四舍五入    return 0;}