#include<iostream>
#include<iomanip>
using namespace std;
int main()
{
    long long int a ;
    
    double b,j;
    cout<<"Cards  Overhang"<<endl;
    while(cin>>a)
    {
        b=0;
        for(j=1;j<=a;j++)
        b+=1.000/(2*j);
        //cout<<"Cards  Overhang"<<endl;
        cout<<setw(5)<<setiosflags(ios::right)<<a<<"  "<<
        setw(8)<<setiosflags(ios::fixed)<<setprecision(3)<<setiosflags(ios::right)
        <<b<<endl;
    }    
    return 0;
}