#include <bits/stdc++.h>
using namespace std;
long long a[101], b, c, k, o, q, w, e, r, t, n, m;
string s, p;
int main() {
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i <= 1000; i++) {
    if (a[n] - a[1] != i && a[1] - a[n] != i)
      for (int j = 1; j < n; j++) {
        if (a[j] - a[j + 1] == i || a[j + 1] - a[j] == i)
          cout << j << " " << j + 1, j = n + 1, i = 100001;
      }
    else
      cout << n << " " << 1, i = 100001;
  }
}
