static void Main(string[] args)
{
int cases = int.Parse(Console.ReadLine());
string[] sol = Console.ReadLine().Split(' ');
int[] soldiers = new int[cases + 1];
for (int i = 0; i < sol.Length; i++)
{
soldiers[i] = int.Parse(sol[i]);
}
soldiers[soldiers.Length - 1] = int.Parse(sol[0]);
int min = 10000000;
string result = "";
for (int i = 0; i < soldiers.Length - 1; i++)
{
int dif = Math.Abs(soldiers[i] - soldiers[i + 1]);
if (dif < min)
{
min = dif;
if(i == sol.Length - 1)
result = (i + 1).ToString() + " 1";
else
result = (i + 1).ToString() + " " + (i + 2).ToString();
}
}
Console.WriteLine(result);
Console.ReadLine();
}