#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define pll pair<long, long>
#define endl "\n"
#define first fs
#define second sc
#define vll vector<ll>

void solve()
{
	ll n;
	cin >> n;
	vll a(n);
	map<ll, vector<ll>> m;
	ll ans[2] = {-1, 0};
	for(ll i = 0; i < n; i++)
	{
		cin >> a[i];
		m[a[i]].push_back(i);
	}
	sort(a.begin(), a.end());
	ll sm = 0;
	for(ll i = 0; i < n; i++)
	{
		if(i != 0 && a[i] == a[i-1]) continue;
		if(sm - m[a[i]][0] > ans[1] - ans[0])
		{
			ans[1] = sm;
			ans[0] = m[a[i]][0];
		}
		if(m[a[i]][m[a[i]].size()-1] > sm) sm = m[a[i]][m[a[i]].size()-1];
	}
	if(ans[0] == -1)
	{
		cout << -1 << endl;
		return;
	}
	cout << ans[0]+1 << " " << ans[1]+1;
}

int main() 
{
	cin.tie(NULL); cout.tie(NULL);
	ios_base::sync_with_stdio(false);
	ll t = 1;
	//cin >> t;
	while(t--) solve();
	return 0;
}