#include <bits/stdc++.h>
using namespace std;
const int MAX = 1e5 + 55;
int x[MAX];
int main() {
  int n;
  cin >> n;
  int a[n + 1];
  for (int i = 1; i <= n; i++) cin >> a[i];
  int min = abs(a[n] - a[1]), k = 1;
  for (int i = 2; i <= n; i++)
    if (abs(a[i] - a[i - 1]) <= min) {
      min = abs(a[i] - a[i - 1]);
      k = i;
    }
  if (k == 1)
    cout << k + n - 1 << " " << k;
  else
    cout << k - 1 << " " << k;
  return 0;
}
