#include <bits/stdc++.h>
#include <iostream>
using namespace std;

int main(){

    int n; cin >> n;
    vector<int>szamok(n+1, 0);
    vector<int>hely(n+1, 0);
    for(int i = 1; i <= n; i++)
    {
        cin >> szamok[i];
        hely[szamok[i]] = i;
    }
    int tav = 0, tav2 = 0, maxi = 0, maxi2 = 0;
    for(int i = 1; i <= n; i++)
    {
        if(i > 1 && tav - hely[i] > maxi2 - maxi)
        {
            maxi = hely[i];
            maxi2 = tav;
        }
        if(hely[i] > tav)
        {
            tav = hely[i];
        }
    }
    if(maxi == 0) cout << "-1";
    else cout << maxi << " " << maxi2;
}