#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
long long a, b;
bitset<32> bit, bit1;
int main() {
	cin >> a >> b;
	bit = a, bit1 = b;
	long long ans = 1, co = 0;
	for (int i = 0; i < 32; i++) {
		if (bit[i] == 1 && bit1[i] == 0) {
			cout << "0" << endl;
			return 0;
		}
		if (bit[i] == 0 && bit1[i] == 1) {
			co++;
		}
	}
	for (int i = 0; i < co - 1; i++) {
		ans *= 2;
	}
	cout << ans << endl;
	return 0;
}