import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner koko = new Scanner(System.in);
       int n = koko.nextInt();
       int[] x = new int[n];
       int[] d = new int[n];
       for(int i = 0; i<n; i++){
           x[i] = koko.nextInt();
       }
       Arrays.sort(x);
       int dis;
       if(n>2){
           dis = x[1]-x[0];
           for(int i = 1; i<n; i++){
               d[i]=x[i]-x[i-1];
               if(dis==0){
                   dis = d[i];
               }else if(dis>d[i]&&d[i]!=0){
                   dis = d[i];
               }
           }
       }else if(n==2){
           dis = x[1]-x[0];
       }else{
           dis = 0;
       }
       System.out.println(dis);
    }
}