func_code_string: #include <bits/stdc++.h>   using namespace std;   int popc(long long int x) {     int cnt = 0;     for (int i = 0; i < 50; i++) {       if ((1ll << i) & x) cnt++;     }     return cnt;   }   int main() {     ios_base::sync_with_stdio(0);     long long int s, x;     cin >> s >> x;     if (s < x) {       cout <<  0 n ;       return 0;     }     if (s == x) {       cout << ((1ll << (popc(s))) - 2) << endl;       return 0;     }     if ((s - x) % 2 == 1) {       cout <<  0  << endl;       return 0;     }     long long int rest = (s - x) / 2;     for (int i = 0; i < 50; i++) {       if ((((1ll << i) & x) != 0) && (((1ll << i) & rest) != 0)) {         cout <<  0 n ;         return 0;       }     }     cout << (1ll << popc(x)) << endl;     return 0;   }   