public class Anchor {
    private Element first;

    public Anchor() {
        this.first = null;
    }

    public Element getFirst() {
        return first;
    }

    public void insertAtTheFront(int x){
        Element newNode = new Element(x);
        newNode.setNext(this.first);
        this.first = newNode;
    }
    public void insertAtTheEnd(int x){
        if(this.first == null){
            this.first = new Element(x);
        }
        else {
            Element currentNode;
            currentNode = this.first;
            while (currentNode.getNext() != null)
                currentNode = currentNode.getNext();
            currentNode.setNext(new Element(x));
        }
    }
    public void removeFirst(){
        if(this.first != null)
            this.first = first.getNext();
    }
    public void removeLast(){
        if(this.first.getNext() != null) {
            Element currentNode;
            currentNode = this.first;
            while (currentNode.getNext().getNext() != null) {
                currentNode = currentNode.getNext();
            }
            currentNode.setNext(null);
        }
        else
            this.first = null;
    }

    @Override
    public String toString() {
        Element currentNode;
        String result = "";
        currentNode = this.first;
        while(currentNode != null){
            result += currentNode.getVal() + ", ";
            currentNode = currentNode.getNext();
        }
        return result;
    }
}