C语言求1/n的和，

#include <stdio.h>

main ()

{

      

      doubleq,m=2,n,sum=0;

   scanf("%lf",&n);

      while(n<=20)

      {

             q=m/n;

             m=m+n;

             n++;

             sum=sum+q;

             printf("%lf\n",sum);

             

      }

      printf("最后sum=%lf",sum);