5 3
 1000 3
 777 17
 4 3
 2 2
 100 4
 10 4
 999 2
 6 4
 1 2
 17 3
 1 4
 26 8
 91 5
 1 3
 1000 2
 20 3
 9 4
 123 5
 1000 1000
 3 2
 3 3
 80 970
 1000 4
 1 1000

7
 1499
 825
 5
 3
 133
 13
 1997
 7
 1
 25
 1
 29
 113
 1
 1999
 29
 11
 153
 1001
 5
 4
 80
 1333
 1

//   http://codeforces.com/problemset/problem/379/A
//   A. New Year Candles
import java.util.Scanner;

public class A03 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
	
		int toot = a;
		int plus = a;
		
		for(int i =1; i<=10 ;i++) {
			
			toot = toot/b;

			plus+=toot;
			if(toot>b)
			toot+=toot%b;

		}
		System.out.println(plus);	
	}
}