import java.util.Scanner;
public class Main {
public static int huaff( int n, int k){
int left = (n + k) / 2;
int sum = 0;
int right = left - k;
if (left - right != k || right <= 0 || left <= 0 || left + right != n){
return sum + 1;
}
return huaff(left, k) + huaff(right, k);
}
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
int k = in.nextInt();
int sum = huaff(n, k);
System.out.println(sum);
}
} 只会第二题