#include<iostream>
using namespace std;
int main(){
	int n,k,i,j,sum;
	cin>>n>>k;
	i=n/k;
	j=i/k;
	if(i<k)
	sum=i*k+n%k+i;
	if(i>=k)
	sum=i*k+n%k+i+j;
	cout<<sum;
	return 0;
}