using System;
using System.Linq;

public class Program
{
	public static void Main()
	{
		int N = int.Parse(Console.ReadLine());
		int[] X = Console.ReadLine().Split().Select(i => int.Parse(i))
			.OrderBy(i => i).Distinct().ToArray();
		int len = X.Length;
		if (len == 1)
		{
			Console.WriteLine(0);
			return;
		}
		int ans = int.MaxValue;
		for (int i = 1; i < len; i++)
		{
			ans = Math.Min(ans, X[i] - X[i - 1]);
		}
		Console.WriteLine(ans);
	}
}