// UUID: c3cdb41a-e3f9-45f2-806f-453d15b4b906
#include <bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    set<int> evszam;
    vector<int> idok(n+1);
    for (int i = 0; i < n; i++) {
        cin >> idok[i];
    }
    int elozomeret=0, utolsoido;
    for (int i = n-1; i >= 0; i--) {
        evszam.insert(idok[i]);
        if (evszam.size() > elozomeret) {
            elozomeret = evszam.size();
            utolsoido = i + 1;
        }
    }
	cout << utolsoido <<"\n";
}