#include <bits/stdc++.h>
using namespace std;
vector<int> mas;
int main() {
  int n;
  cin >> n;
  mas.resize(n);
  for (int i = 0; i < n; ++i) scanf("%d", &mas[i]);
  mas.push_back(mas[0]);
  int best = -1, it1, it2;
  for (int i = 0; i < n; ++i)
    if (best == -1 ||
        best > ((mas[i] - mas[i + 1] < 0) ? -(mas[i] - mas[i + 1])
                                          : mas[i] - mas[i + 1])) {
      best = ((mas[i] - mas[i + 1] < 0) ? -(mas[i] - mas[i + 1])
                                        : mas[i] - mas[i + 1]);
      it1 = i + 1;
      it2 = i + 2;
    }
  if (it2 == n + 1) it2 = 1;
  cout << it1 << " " << it2 << endl;
  return 0;
}
