import java.util.Arrays;
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];
		int ans = 1001001001;
		for(int i = 0 ; i < n ; i++) x[i] = sc.nextInt();
		Arrays.sort(x);
		for(int i = 0 ; i < n - 1 ; i++) {
			if(Math.abs(x[i + 1] - x[i]) != 0) {
				ans = Math.abs(x[i + 1] - x[i]);
			}
		}
		if(ans == 0 || ans == 1001001001) {
			System.out.println(0);
		} else {
			System.out.println(ans);
		}
 	}
}