#include<iostream>
#include<stdio.h>
using namespace std;
int main()
{
	int i,j,mid=1;
	int sum;
	while(cin>>i>>j)
	{
		sum=i;
		while(i/j)
		{
			sum+=i/j;
			i=i/j+i%j;
		}
		cout<<sum<<endl;
	}

	return 0;
}