#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <atcoder/modint>
using namespace std;
using i32 = int;
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(int i=0; i<(int)(n); i++)
const i64 INF = 1001001001001001001;

using Modint = atcoder::static_modint<998244353>;

int main(){
    string A, B; cin >> A >> B;
    if(A.size() < B.size()) swap(A, B);
    int of = A.size() - B.size();
    rep(i,B.size()) A[i+of] = ((A[i+of] - '0') + (B[i] - '0')) % 2 + '0';
    i64 ans = 0;
    for(char c : A) ans = ans * 2 + (c - '0');
    cout << ans << endl;
    return 0;
}



struct ios_do_not_sync{
    ios_do_not_sync(){
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
    }
} ios_do_not_sync_instance;