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

class Program
{
    static void Main(string[] args)
    {
        int n = int.Parse(Console.ReadLine());
        int[] x = Console.ReadLine().Split().Select(xx => int.Parse(xx)).ToArray();
        Array.Sort(x);
        int min = 1000001;

        for (int i = 0; i < n - 1; i++)
        {
            if (x[i] != x[i + 1])
            {
                min = Math.Min(min, x[i + 1] - x[i]);
            }
        }

        if (min == 1000001)
        {
            min = 0;
        }

        Console.WriteLine(min);
        Console.Read();
    }
}