import java.util.*;

public class Run {
    public static void main (String arg[]) {
        Scanner scan = new Scanner(System.in);
        int N = scan.nextInt();
        int[] X = new int[N];
        for (int i = 0; i < N; i++) {
            X[i] = scan.nextInt();
        }
        Arrays.sort(X);
        int min = X[1] - X[0];
        int tmp;
        for (int i = 1; i < N-1; i++) {
            tmp = X[i+1] - X[i];
            if ((min==0 && tmp!=0) || min > tmp) min = tmp;
        }
        System.out.println(min);
    }
}