POJ 1607 Deck G++

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
	int n;
	int flag=0;
	while(scanf("%d",&n)!=EOF)
	{
		double sum=0;
		for(int i=1;i<=n;i++)
		{
			sum=sum+1.0/(i*2);
		}	
		if(flag==0)
		{
			flag=1;
			printf("Cards  Overhang\n");
		}	
		printf("%5d  %8.3f\n",n,sum);
	}

	return 0;
}