/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		LinkedList <Integer> list = new LinkedList<Integer>() ;
        list.add(2); 
        list.add(3); 
        list.add(4); 
        list.add(1); 
        list.add(0); 
        list.addAll(list);
        System.out.println(list);
	}
}

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