#include <iostream>
#include <vector>

using namespace std;

int main()
{
	int n, mini = 100001, maxi = -100001;
	cin >> n;
	vector<int> v(n + 1);
	vector<int> ma(n + 1);
	vector<int> mi(n + 1);
	
	for (int i = 1; i <= n; ++i) {
		cin >> v[i];

		if (v[i] > maxi) {
			maxi = v[i];
		}
		ma[i] = maxi;
	}
	for (int j = n; j > 0; --j) {
		if (v[j] < mini) {
			mini = v[j];
		}
		mi[j] = mini;
	}

	int i = 1, j = 1, p = -1, p2 = -1, t, maxit = 0;
	while (j <= n && i <= n) {
		if (ma[i] > mi[j]) {
			++j;
		}
		else {
			t = j - 1 - i;
			if (t > maxit) {
				maxit = t;
				p = j - 1;
				p2 = i;
			}
			while (ma[i] < mi[j]) ++i;
		}
	}

	if (p == -1) {
		cout << "-1";
	}
	else {
		cout << p2 << " " << p;
	}
}