import java.util.Arrays;
import java.util.Scanner;

public class No135 {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        int count = s.nextInt();
        int[] pos = new int[count];
        for (int i = 0; i < count; i++) {
            pos[i] = s.nextInt();
        }
        pos = Arrays.stream(pos).distinct().sorted().toArray();
        if (pos.length < 2) {
            System.out.println(0);
            return;
        }
        int min = Integer.MAX_VALUE;
        for (int i = 1; i < pos.length; i++) {
            int tmp = pos[i] - pos[i - 1];
            if (min > tmp) {
                min = tmp;
            }
        }
        System.out.println(min);
    }
}