Implement Stack using 2 Queues

Costly Push Operation 

public class StackUsingTwoQueues {


    Queue<Integer> queue1 = new LinkedList<>();
    Queue<Integer> queue2 = new LinkedList<>();

    public void push(Integer element)
    {
        if(element==null)
        {
            return;
        }
        while(!queue1.isEmpty())
        {
            queue2.add(queue1.poll());
        }

        queue1.add(element);

        while(!queue2.isEmpty())
        {
            queue1.add(queue2.poll());
        }
    }

    public int pop()
    {
        return queue1.poll();
    }

    public static void main(String args[])
    {
        StackUsingTwoQueues stackUsingTwoQueus = new StackUsingTwoQueues();
        stackUsingTwoQueus.push(1);
        stackUsingTwoQueus.push(2);
        stackUsingTwoQueus.push(3);
        stackUsingTwoQueus.push(4);
        stackUsingTwoQueus.push(5);

        System.out.println(stackUsingTwoQueus.pop());
        System.out.println(stackUsingTwoQueus.pop());
        System.out.println(stackUsingTwoQueus.pop());
        System.out.println(stackUsingTwoQueus.pop());
        System.out.println(stackUsingTwoQueus.pop());

    }
}

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