import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int yan=sc.nextInt();
        int yandi=sc.nextInt();
        int chouyan=yan;
        int yanslip=yan;
        while (yanslip>=yandi){
            chouyan+=yanslip/yandi;
            yanslip=yanslip%yandi+yanslip/yandi;
        }
        System.out.println(chouyan);
    }
}