<swustoj>?id=42 平方和与倒数和

#include <stdio.h>
int main()
{
    double sum(int a,int b,double c);
    int a,b;
    double c;
    scanf("%d %d %lf",&a,&b,&c);
    printf("%.2lf\n",sum(a,b,c));
    return 0;
}
double sum(int a,int b,double c)
{
    int i;
    int sum_1=0,sum_2=0;
    double sum_3=0;
    sum_1=a*(a+1)/2;
    for(i=1;i<=b;i++)
    {
        sum_2+=i*i;
    }
    for(i=1;i<=c;i++)
    {
        sum_3+=1/(double)i;
    }
    return sum_1+sum_2+sum_3;
}