zoj1216

#include<stdio.h>
int main()
{
  int n,i;
  float a,sum=0,b;
  printf("# Cards  Overhang\n");
  while(scanf("%d",&n)==1)
  {
     for(i=1;i<=n;i++)
     {
       b=2*i;
       sum=sum+1/b;
     }
     printf("%5d%10.3f\n",n,sum);
     sum=0;
  }
  return 0;
}