#include <bits/stdc++.h>
using namespace std;
const int INF = 1029384756;
const double PI = acos(-1);
const double EPS = 0.0000000304;
long long A, B, C;
int main() {
  scanf("%I64d%I64d%I64d", &A, &B, &C);
  if ((A % 2) == (B % 2) && (B % 2) == (C % 2)) {
    printf("%I64d", A + B + C - max(A, max(B, C)) - min(A, min(B, C)));
  } else if (A % 2 == B % 2) {
    printf("%I64d", max(A, B));
  } else if (A % 2 == C % 2) {
    printf("%I64d", max(A, C));
  } else {
    printf("%I64d", max(B, C));
  }
  return 0;
}
