#include<iostream>
#include<vector>
#include<algorithm>
#include<cmath>
#include<string>
#include<iomanip>
#include<numeric>
#include<queue>
#include<deque>
#include<stack>
#include<set>
#include<map>
#include<random>
using namespace std;
typedef long long ll;
const int mod=998244353;
int main(){
	int a,b;
	cin>>a>>b;
	if(a&~b)
		cout<<0<<endl;
	else
		cout<<(1<<max(__builtin_popcount(~a&b)-1,0))<<endl;
}