#include<bits/stdc++.h>
using namespace std;

int main(){
	int A, B, C;
  	cin >> A >> B;
  	C = A + B;
    string D = to_string(C);
  	for(int i = 0; i < D.size(); i++){
    if(D.at(i) == '2') D.at(i) = '0';
    }
  	C = stoi(D, 0, 2);
  	cout << C << endl;
}