#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define endl "\n"
using namespace std;
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    ll x,y,z;
    cin>>x>>y>>z;
    if(x%2==y%2) cout << z<< endl;
    else if (y%2==z%2) cout << x<< endl;
    else if(x%2==z%2) cout << y << endl;
    return 0;
}