求奇数分之一序列前N项和 (15 分)

Question

Answer 1

#include <stdio.h>
int main()
{
    int i,N;
    double sum = 0;
    scanf("%d",&N);
    for(i=1;i<=N;i++)
        sum += 1.0/(2*i-1);
    printf("sum = %.6lf",sum);
    return 0;
}