using System;
using System.Linq;
class Program {
    static void Main() {
        int n = int.Parse(Console.ReadLine());
        int min = 1000001;
        if (n < 2) {
            min = 0;
        } else {
            var q = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToList();
            for (int i = 0; i < n - 1; i++) {
                if (q[i] == q[i + 1]) continue;
                int d = Math.Abs(q[i] - q[i + 1]);
                if (d < min) min = d;
            }
            if (min == 1000001) min = 0;
        }
        Console.WriteLine(min);
    }
}