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

class Main135 {
	
	public static void out (Object out) {
		System.out.println(out);
	}
	
	public static void main (String[] args) throws IOException {
		BufferedReader br = 
			new BufferedReader(new InputStreamReader(System.in));
		
		int ans = Integer.MAX_VALUE;
		int n = Integer.parseInt(br.readLine());
		String[] line = br.readLine().split(" ");
		ArrayList<Integer> list = new ArrayList<Integer>();
		
		for (int i = 0; i < n; i++) {
			int m = Integer.parseInt(line[i]);
			if (!list.contains(m)) list.add(m);
		}
		Collections.sort(list);
		
		for (int i = 1; i < list.size(); i++) {
			ans = Math.min(ans , list.get(i) - list.get(i - 1));
		}
		
		out(list.size() == 1 ? 0 : ans);
		
	}
}