import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int[] b=new int[n];
        int[] a = new int[n];
        int i=0,j=0,k=0,min=0;
        for(int a_i=0; a_i < n; a_i++){
            a[a_i] = in.nextInt();
        }
        // your code goes here
        while(i<n)
            {
	            j=i+1;
	            while(j<n)
	              {
		            b[k]=Math.abs(a[i]-a[j]);
		            j++;
		            k++;
	            }
            i++;
        }
min=b[0];
for(i=0;i<b.length;i++)
{
		if(min>b[i])
	{
		min=b[i];
	}
}
System.out.println(min);

    }
}