#include <bits/stdc++.h>
using namespace std;
int a[500];
int main() {
  int n, even = 0, odd = 0;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    if (a[i] % 2 == 0)
      even++;
    else
      odd++;
  }
  for (int i = 0; i < n; i++) {
    if (even == 1 && a[i] % 2 == 0) {
      cout << i + 1 << endl;
      break;
    }
    if (odd == 1 && a[i] % 2 == 1) {
      cout << i + 1 << endl;
      break;
    }
  }
}
