#include <bits/stdc++.h>
using namespace std;
long long a, b, c;
int main() {
  ios::sync_with_stdio(false);
  cin >> a >> b >> c;
  long long m = min(a, b);
  if (a != b) cout << 2 * (c + m) + 1 << endl;
  if (a == b) cout << 2 * (c + a) << endl;
  return 0;
}
