#include<iostream>
#include<iomanip>
using namespace std;
int main()
{
	int n;	
	cout<<"Cards  Overhang"<<endl;
	while(cin>>n)
		{ 
			int i;
			double sum=0.0;
			for( i=1;i<n+1;i++)
			{
				sum+=1.0/(2*i);
			}
		
			cout<<setiosflags(ios::right)<<setw(5)<<n;
			cout<<setiosflags(ios::fixed)<<setw(10)<<setprecision(3)<<sum<<endl;
	}
	return 0;
}