import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int[] x = new int[n];

        for (int i = 0; i < n; i++) {
            x[i] = sc.nextInt();
        }

        int first = x[0];
        //int i = 1;
        int min = Integer.MAX_VALUE;

        for (int i = 1; i < n; i++) {
            int second = x[i];

            if (Math.abs(first - second) < min && Math.abs(first - second) != 0) {
                min = Math.abs(first - second);
            }

            first = second;

        }

        System.out.println(min);

    }

}