import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class No_166 {
	static int shortestDistance(ArrayList list, int i1, int i2, int m) {
		int num1 = (int) list.get(i1);
		int num2 = (int) list.get(i2);
		int min = m;
		if (num1 != num2) {
			min = Math.min(m, Math.abs(num1 - num2));
		}
		if (i2 >= list.size() - 1) {
			return min;
		} else {
			return shortestDistance(list, ++i1, ++i2, min);
		}
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		ArrayList<Integer> list = new ArrayList<Integer>();
		int n = sc.nextInt();

		for (int i = 0; i < n; i++) {
			list.add(sc.nextInt());
		}

		Collections.sort(list);
		int ans = shortestDistance(list, 0, 1, Integer.MAX_VALUE);
		System.out.println(ans);
		sc.close();

	}

}