#include <bits/stdc++.h>
template <typename T>
T gcd(T a, T b) {
  return b ? gcd(b, a % b) : a;
}
template <typename T>
T lcm(T a, T b) {
  return a * b / gcd(a, b);
}
using namespace std;
int a, b;
int menor = INT_MAX;
int main() {
  ios_base::sync_with_stdio(0);
  int n;
  cin >> n;
  vector<int> v(n);
  for (int i = 0; i < n; i++) cin >> v[i];
  for (int i = 0; i < n; i++) {
    if (abs(v[i] - v[(i + n - 1) % n]) < menor) {
      menor = abs(v[i] - v[(i + n - 1) % n]);
      a = (i + n - 1) % n + 1;
      b = i + 1;
    }
  }
  cout << a << " " << b << "\n";
  return 0;
}
