func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     unsigned long long a, b, x, y;     cin >> a >> b;     x = (a - b) / 2;     y = x + b;     if ((x > y) || (x + y != a) || (x ^ y) != b)       cout <<  -1  << endl;     else       cout << x <<     << y << endl;     return 0;   }   