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

int main() {
	int x,y,z,cnt=0;
	cin>>x>>y>>z;
	int a=x%2,b=y%2,c=z%2;
	if(a==b)cout<<z<<endl;;
	if(b==c)cout<<x<<endl;;
	if(c==a)cout<<y<<endl;
//	cout<<cnt<<endl;

}