#include <bits/stdc++.h>
using namespace std;
#define ll long long
ll myXOR(ll x, ll y)
{
    ll res = 0; // Initialize result

    // Assuming 32-bit Integer
    for (ll i = 31; i >= 0; i--)
    {
        // Find current bits in x and y
        bool b1 = x & (1 << i);
        bool b2 = y & (1 << i);

        // If both are 1 then 0 else xor is same as OR
        bool xoredBit = (b1 & b2) ? 0 : (b1 | b2);

        // Update result
        res <<= 1;
        res |= xoredBit;
    }
    return res;
}

int main(){
    long long int  a=5,b=3;
    cin>>a>>b;
    long long int  c=(a|b)&(~a|~b);
    cout<<(myXOR(a,b))<<endl;
    return 0;
}