#include <iostream>
#include <vector>
#include <algorithm>
#include <unordered_map>
#define ll long long
using namespace std;

int main() {
    ll x, y, z;
    cin>>x>>y>>z;
    ll remx = x%2;
    ll remy = y%2;
    ll remz = z%2;
    if(remx == remy) cout<<z<<endl;
    else if(remy == remz) cout<<x<<endl;
    else if(remz == remx) cout<<y<<endl;
}