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

public class Main {
    public static void main(String[] a) {
        Scanner s = new Scanner(System.in);
        int N=s.nextInt(),i=0,d,m=Integer.MAX_VALUE;
        int[] X=new int[N];
        for(;i<N;)X[i++]=s.nextInt();
        Arrays.sort(X);
        for(i=0;i<N-1;i++){
int e = X[i] - X[i+1];
if (e < 0) e *= -1;
if (e != 0 && e < m) {
m = e;
}
        }
        System.out.println(m==Integer.MAX_VALUE?0:m);
    }
}