#include <iostream>
using namespace std;
int main(void) {
	int n, k;
	cin >> n >> k;
	int a = 1 << k;
	int b = 1 << n;
	int x = a;
	int ans = 0;
	if (b >= a) ans = (b - a) / a + 1;
	cout << ans << endl;
	return 0;
}