#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import collections
import itertools


IMPOSSIBLE = [-1]


def is_kadomatsu(triplet):
    a, b, c = triplet.values()
    if a == b or b == c or c == a:
        return False
    elif b == max(a, b, c) or b == min(a, b, c):
        return True
    else:
        return False


def judge(sequence):
    if len(sequence) < 3:
        return IMPOSSIBLE
    else:
        for t_triplet in itertools.combinations(sequence.items(), 3):
            triplet = collections.OrderedDict(t_triplet)
            if not is_kadomatsu(triplet):
                continue
            else:
                rest_sequence = collections.OrderedDict(
                    p for p in sequence.items() if p[0] not in triplet)
                result = judge(rest_sequence)
                if result == IMPOSSIBLE:
                    return triplet
                else:
                    continue
        else:
            return IMPOSSIBLE


if __name__ == "__main__":
    n = int(input())
    ks = collections.OrderedDict(enumerate(map(int, input().split())))
    print(*judge(ks))