using System;

public class Program {
	public static void Main(string[] args) {
		Console.ReadLine(); // n
		string[] x = Console.ReadLine().Split(' ');
		int min = 0;
		for (int i = 1; i < x.Length; i++) {
			int dist = Math.Abs(int.Parse(x[i])-int.Parse(x[i-1]));
			if (dist < min && dist != 0 || min == 0) {
				min = dist;
			}
		}
		Console.WriteLine(min);
	}
}