import java.util.Arrays;
import java.util.Scanner;
public class No135 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int[] x = new int[n];
		// 全ての地点を配列に格納
		for(int i = 0; i < n; i++){
			x[i] = sc.nextInt();
		}
		sc.close();
		// 地点を昇順にソート
		Arrays.sort(x);
		int min = 9999999;
		for(int i = 0; i < (n - 1); i++){
			if((x[i] != x[i + 1]) && (x[i + 1] - x[i]) < min){
				min = x[i + 1] - x[i];
			}
		}
		if(min == 9999999){
			min = 0;
		}
		System.out.println(min);
	}
}