#include <bits/stdc++.h>
int main() {
  int N;
  scanf("%d", &N);
  int a[N];
  scanf("%d", &a[0]);
  scanf("%d", &a[1]);
  int min = ((a[1] - a[0]) >= 0 ? (a[1] - a[0]) : (-1 * (a[1] - a[0])));
  int minindex = 0;
  for (int i = 2; i < N; i++) {
    scanf("%d", &a[i]);
    if (min > ((a[i] - a[i - 1]) >= 0 ? (a[i] - a[i - 1])
                                      : (-1 * (a[i] - a[i - 1])))) {
      min = ((a[i] - a[i - 1]) >= 0 ? (a[i] - a[i - 1])
                                    : (-1 * (a[i] - a[i - 1])));
      minindex = i - 1;
    }
  }
  if (min >
      ((a[0] - a[N - 1]) >= 0 ? (a[0] - a[N - 1]) : (-1 * (a[0] - a[N - 1])))) {
    min =
        ((a[0] - a[N - 1]) >= 0 ? (a[0] - a[N - 1]) : (-1 * (a[0] - a[N - 1])));
    minindex = N - 1;
  }
  printf("%d %d\n", minindex + 1, 1 + (minindex + 1) % N);
}
