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






			import java.io.*;
			public class lastA
			{
				public static void main(String args[])
				throws IOException
				{
					BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
					PrintWriter pw=new PrintWriter(System.out);
					String in[]=br.readLine().split(" ");
					int a=Integer.parseInt(in[0]);
					int b=Integer.parseInt(in[1]);
					int sum=a;
					while(a/b!=0)
					{
						sum+=a/b;
						a/=b;
					}
					System.out.println(sum);
					
				}
			}