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

public class Main{
	
	
	public static void main(String args[])throws Exception{
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int min = 1234567;
		int[] X = new int[N];
		for(int i=0;i<N;i++){
			X[i] = sc.nextInt();
		}
		Arrays.sort(X);
		for(int i=0;i<N-1;i++){
			if(X[i]!=X[i+1]){
				min = Math.min(min, X[i+1]-X[i]);
			}
		}
		if(min==1234567){
			min=0;
		}
		System.out.println(min);
	}
	

}