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();
		for(int i = 0 ; i < n ; i++) {
			for(int j = i + 1 ; j < n ; j++) {
				if(Math.abs(x[i] - x[j]) != 0) {
					ans = Math.min(ans, Math.abs(x[i] - x[j]));
				}
			}
		}
		System.out.println(ans);
 	}
}