#include <bits/stdc++.h>
using namespace std;
const long long N = 1e6 + 10;
const long long INF = 1e18;
const long long inf = -1e18;
const long long MOD = 1e9 + 7;
const long long base = 1000 * 1000 * 1000;
int gcd(int a, int b) {
  while (b) {
    a %= b;
    swap(a, b);
  }
  return a;
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
void solve() {
  long long n;
  cin >> n;
  long long a[n];
  for (int i = 0; i < n; ++i) cin >> a[i];
  long long mini = 1e9 + 7;
  long long s, e;
  for (long long i = 0; i < n - 1; i++) {
    if (mini > abs(a[i] - a[i + 1])) {
      mini = abs(a[i] - a[i + 1]);
      s = i + 1;
      e = i + 2;
    }
  }
  if (mini > abs(a[0] - a[n - 1])) {
    s = 1;
    e = n;
  }
  cout << s << " " << e << " ";
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  solve();
}
