import java.util.*;

public class Test38{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int W = sc.nextInt();
		int D = sc.nextInt();
		int Yaruki;
		for(int i=D; i>1; i--){
			Yaruki = W/(D*D);
			W -= Yaruki; 
		}
		System.out.println(W);
    }
}