#include<stdio.h>
int main()
{int n,k,i,a,b;
scanf("%d %d",&n,&k);
double sum=0;
double sus=0;
for(i=1;i<=n;i++)
{if(i%k)
{sum+=i;
a++;}
else {sus+=i;b++;}}

printf("%.1lf %.1lf",sum/a,sus/b);
return 0;}