using System;
using System.Collections.Generic;
using System.Linq;

namespace No135
{
	class MainClass
	{
		public static void Main (string[] args)
		{
			Convert.ToInt32 (Console.ReadLine ());
			var data = Console.ReadLine ().Split (' ').Select (v => Convert.ToInt32 (v)).ToArray ();
			Array.Sort (data);
			var minDistance = int.MaxValue;
			for (int i = 0; i < data.Length-1; i++) {
				var distance = data [i + 1] - data [i];
				if (distance != 0) {
					minDistance = Math.Min (minDistance, distance);
				}
			}
			if (minDistance == int.MaxValue) {
				Console.WriteLine ("0");
				return;
			}
			Console.WriteLine (minDistance.ToString ());
		}
	}
}