  import java.util.Random; 

  /** 
     This class contains utility methods for array manipulation. 
  */ 
  public class ArrayUtil 
  { 
     /** 
       Creates an array filled with random values. 
   @param length the length of the array 
   @param n the number of possible random values 
   @return an array filled with length numbers between 
       0 and n - 1 
    */ 
    public static int[] randomIntArray(int length, int n) 
    { 
   int[] a = new int[length]; 
   for (int i = 0; i < a.length; i++) 
      a[i] = generator.nextInt(n); 
 
   return a; 
    } 
 
  private static Random generator = new Random(); 
 }
