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

public class Candles{
	public static void main(String []args){
		
		java.util.Scanner scan=new java.util.Scanner(System.in);
		int a=scan.nextInt();
		int b=scan.nextInt();
		int count=0,rem=0;
		while(a!=0){
			count+=a;
			a/=b;
			rem+=a%b;
			if(rem>=b){
				a+=rem/b;
				rem=rem%b;
			}
		}
		System.out.println(count);
		
	}
}