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[] a = new int[n];
        int mindiff = Integer.MAX_VALUE;
        
        for(int a_i=1; a_i < n; a_i++){
            a[a_i] = in.nextInt();
            int diff = Math.abs(a[a_i]-a[a_i-1]);
            if (diff < mindiff){
                mindiff = diff;
            }
          
           
            
        }
        System.out.print(mindiff);
        
        
        // your code goes here
    }
}