text: #include <iostream>
  #include <string>
  #include <vector>
  #include <sstream>
  #include <algorithm>
  #include <map>
  #include <set>
  #include <hash_map>
  #include <hash_set>
  #include <queue>
  #include <stack>
  
  using namespace std;
  
  class Solution {
  public:
    int getSum(unsigned int a, unsigned b) {
      while (b) {
        auto c = a^b;
        b = (a & b) << 1;
        a = c;
      }
      return a;
    }
  };
  
  int main() {
    Solution solution;
    auto v = solution.getSum(-1, 1);
    return v;
  }