#include <cstdio> #include <cstring> #include <iostream> #include <string> #include <cmath> #include <bitset> #include <vector> #include <map> #include <set> #include <queue> #include <deque> #include <algorithm> #include <complex> #include <unordered_map> #include <unordered_set> #include <random> #include <cassert> #include <fstream> #include <utility> #include <functional> #include <time.h> #include <stack> #include <array> #define popcount __builtin_popcount using namespace std; typedef long long int ll; typedef pair<ll, ll> P; int main() { int a, b; cin>>a>>b; ll ans=1; for(int i=0; i<31; i++){ int x=((a>>i)&1), y=((b>>i)&1); if(x==0 && y==1) ans*=2; else if(x==1 && y==0){ cout<<0<<endl; return 0; } } if(a==b){ cout<<1<<endl; }else{ ans/=2; cout<<ans<<endl; } return 0; }