6.16.12

输出结果

我的解答
// 6.16.12
#include <stdio.h>
#include <math.h>
int main(void)
{
    int loop;
    double sum = 0;
    double signedsum = 0;
    int maxloop;

    printf("请输入次数（即项数）： ");
    while (scanf("%d", &maxloop) == 1 && maxloop > 0)
    {
        for (loop = 1;loop <= maxloop;loop++)
        {
            sum = sum + 1.0/(loop * 1.0);
            signedsum = signedsum + 1.0/(loop * 1.0) * pow(-1, (loop - 1));
        }
        printf("sum is %.20f
", sum);
        printf("signedsum is %.20f
", signedsum);
    }
    return 0;
}