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

#define ll long long
#define endl '\n'
#define print(v) for(auto e:v) cout<<e<<" "; cout<<endl;

void solve() {
    int a,b,c;cin >>a >>b >> c;
    map<ll,ll>mpp;
    if( a%2 == b% 2){
        cout<< c << endl;
    }
    else if( a%2 == c%2){
        cout << b << endl;
    }
    else if(b%2 == c%2) {
        cout << a << endl;
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int t = 1;// cin >> t;
    while(t--){
        solve();
    }
    return 0;
}