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

int main() {
	int n; cin >> n;
	vector<int> nums(n);
	for(int i = 0; i < n; i++) cin >> nums[i];
	vector<int> x(n);
	x[n-1] = nums[n-1];
	for(int i = n-2; i >= 0; i--) x[i] = min(nums[i], x[i+1]);
	int a = -1000000;
	int ans = 0;
	int b = 0;
	int e=-1,f=-1;
	for(int i = 0; i < n-1; i++) {
		if(nums[i] > a) {
			a = nums[i];
			while(b < n && x[b] < nums[i]) b++;
			if(b-i-1 > ans) {
				ans = b-i-1;
				e = i+1; f = b;
			}
		}
	}
	if(e != -1) cout << e <<  " "<< f;
	else cout << -1;
}