25A

#include<bits/stdc++.h>
#define lli long long int
#define vi vector<int>
#define vlli vector<lli>
#define pii pair<int,int>
#define vpi vector<pii>
#define mp unordered_map<char,int>
#define rep(i,a,b) for(int i=a;i<b;i++)
#define ff first
#define ss second
 
#define MOD1 1000000007
#define MOD2 1000000009
using namespace std;
signed main(){
  int n,mn,plus=0,minus=0;cin>>n;
  int arr[100];
  for (int i=1;i<=n;i++){
   cin>>arr[i];
    if (arr[i]%2==0) plus++;
    else minus++;
  }
  for(int i=1;i<=n;i++){
    if (plus>minus){
      if (arr[i]%2!=0){
        mn=i;
      }}
    else{
      if (arr[i] %2==0)
        mn=i;
    }
  }
  cout<<mn<<"\n";
  return 0;
}