First Interview question - Java, Java

First Interview question - Java

/**
Write an algorithm that will find the first duplicate in a list on the page - {6, 3, 1, 4, 7, 4, 2, 8, 9, 2}
For example we would return 4, for the list above.
*/

import java.util.*;
import java.lang.*;

class Rextester
{ 
    static int[] myList = {6, 3, 1, 4, 7, 4, 2, 8, 9, 2};
    
    public static void main(String args[])
    {
        int result = findDuplicate();
        System.out.println((result > 0)? "Found the first duplicate: " + result : "First duplicate not found");
    }
    
    static int findDuplicate() {
        Hashtable<Integer, Integer> myHash = new Hashtable<Integer, Integer>();
        
        for (int i = 0; i < myList.length; i++) {
            if (!myHash.contains(new Integer(myList[i]))) {
                // add this value to myHash
                myHash.put(i, myList[i]);
            }
            else if (myHash.containsValue(new Integer(myList[i]))) {
                // found the duplicate
                return myList[i];
            }            
        }
        return -1;
    }
}


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