如何实现用三中实现循环的语句编写程序实现求1-1/2＋1/3-1/4＋……＋1/99-1/100的值

如何实现用三中实现循环的语句编写程序实现求1-1/2＋1/3-1/4＋……＋1/99-1/100的值

#include <stdio.h>
#include <math.h>
void main()
{
   //for
    double sum1 = 0;
    for (int i = 1; i <= 100; i++)
        sum1 += pow(-1, (double)i - 1) * (1.0 / i);
    printf("%lf\n", sum1);
    //while
    double sum2 = 0;
    int j = 1;
    while (j <= 100)
    {
        sum2+= pow(-1, (double)j - 1) * (1.0 / j);
        j++;
    }
    printf("%lf\n", sum2);
    //if
    double sum3 = 0;
    int k = 1;
    L1:
    if (k >= 1 && k <= 100)
    {
        sum3 += pow(-1, (double)k - 1) * (1.0 / k);
        k++;
        goto L1;
    }
    printf("%lf\n", sum3);
    return 0;
}

供参考：

#include <stdio.h>
int main()
{
    int i=1,n=100,k=1;
    double s=0;
    while(i <= n){
          s+= 1.0*k/i;
          k*= -1;
          i++;
    }
    printf("s=%f",s);
    return 0;
}

 void main() {
    int i = 1;
    double s = 0;
    for(i = 1; i <= 100; i++)
    {
        s += n(i) * 1 / (double)i;
    }
    printf(s);
}

int n(int n)
{
    int i = 1;
    int s = -1;
    for(i = 1; i<= n; i++) {
        s *= -1;
    }
    return s;
}