#include <bits/stdc++.h>
using namespace std;
int main()
{	int n,k;
double sum1,sum2,a=0,b=0;
	cin>>n>>k;
	for(int i=1;i<=n;i++)
	{
		if(i%k==0)
		{
			sum1+=i;
			a++;
		}
		
		
		else
		{
			sum2+=i;
			b++;
			
		}
		
	
	}
	cout<<fixed<<setprecision(1)<<sum1/a<<endl;
	cout<<fixed<<setprecision(1)<<sum2/b<<endl;		
	return 0;
}