#include <bits/stdc++.h>
using namespace std;
const double PI = acos(-1.0);
using namespace std;
const long long MOD = 1000000007;
const long long INF = 1000000000000000000LL;
void DBG() { cerr << "]" << endl; }
template <class H, class... T>
void DBG(H h, T... t) {
  cerr << to_string(h);
  if (sizeof...(t)) cerr << ", ";
  DBG(t...);
}
void solve() {
  long long min_height = INF;
  int n;
  cin >> n;
  vector<int> heights;
  for (int i = 0; i < n; i++) {
    int h;
    cin >> h;
    heights.push_back(h);
  }
  int best1;
  int best2;
  for (int i = 0; i < n - 1; i++) {
    int diff = abs(heights[i] - heights[i + 1]);
    if (diff < min_height) {
      min_height = diff;
      best1 = i + 1;
      best2 = i + 2;
    }
  }
  if (abs(heights[heights.size() - 1] - heights[0]) < min_height) {
    best1 = heights.size();
    best2 = 1;
  }
  cout << best1 << " " << best2 << endl;
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
