// kesos.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <map>
#include <vector>
using namespace std;
map<int, int> gyt;
vector<int>years;
int main()
{
    int n;
    cin >> n;
    years.resize(n);
    for (int i = 0; i < n; i++) {
        cin >> years[i];
        gyt[years[i]]++;
    }
    int x = 0;
    int kev;
    while (gyt[years[x]] != 0) {
        gyt[years[x]]--;
        if (gyt[years[x]] == 0) {
            kev = x;
            break;
        }
        x++;
    }
    cout << kev+1;
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file