import java.util.Scanner;
public class _04_调手表 {
	public static Scanner in = new Scanner(System.in);
	public static void main(String[] args) {
		int n = in.nextInt(), k = in.nextInt();
		int ans = (n - 1) / k + (n - 1) % k;
		System.out.println(ans);
	}
}