import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.Scanner;
import java.util.TreeSet;

public class Main {
	
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		
		final int N = sc.nextInt();
		
		TreeSet<Integer> set = new TreeSet<Integer>();
		for(int i = 0; i < N; i++){
			set.add(sc.nextInt());
		}
		ArrayList<Integer> list = new ArrayList<Integer>(set);
		
		int min = Integer.MAX_VALUE;
		for(int i = 0; i < list.size() - 1; i++){
			min = Math.min(min, Math.abs(list.get(i) - list.get(i + 1)));
		}
		if(min == Integer.MAX_VALUE){
			min = 0;
		}
		
		System.out.println(min);
		
	}
}