Find unique numbers in an array.

Question

How would I find unique numbers in an array by using only one array?

Answer 1

At the above codes, I use the String representation of the number that I want to find. I know that it is an easy example but it can give you an idea that how Hash works in Java.
Give symbols(aliases) to your numbers which helps you to remember the each specific number, so you can find specific number by only using its symbol(nickname) instead of using its location which is more difficult to remember.
import java.util.*;
* ...Hashdescription...
* @author  ...yourname...
* @version 1.00, 2006/05/19
public class Hash
     // properties
     ArrayList keys;
     ArrayList values;
     // constructors
     public Hash(){
          keys = new ArrayList();
          values = new ArrayList();
     // methods
     public void add(int val){
          values.add(new Integer( val));
          keys.add("" + val);
     public int get(String key){
          int index = keys.indexOf(key);
          return ((Integer)(values.get(index )) ). intValue();
     public static void main( String[] args)
          Hash list = new Hash();
          list.add(1);
          list.add(2);
          list.add(3);
          list.add(4);     
          list.add(5);
          list.add(6);
          list.add(7);
          list.add(8);
          list.add(9);
          System.out.println(list.get("3"));
} // end of class Hash