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

public class Main {
	public static void main(String[] args) {

		try {
			Scanner scan = new Scanner(System.in);
			int N = scan.nextInt();
			ArrayList<Integer> x = new ArrayList<>(N);
			int ans = Integer.MAX_VALUE;

			for (int i = 0; i < N; ++i) {
				x.add(scan.nextInt());
			}
			x.sort(null);

			for (int i = 0; i < N - 1; ++i) {

				if (!x.get(i).equals(x.get(i + 1))) {
					if (Math.abs(x.get(i) - x.get(i + 1)) < ans) {
						ans = Math.abs(x.get(i) - x.get(i + 1));
					}
				}
			}

			if (ans == Integer.MAX_VALUE) {
				ans = 0;
			}
			System.out.println(ans);

			scan.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}