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Doubly Linked List - Add To Head

A Pen By kofi

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JS

            
              DoublyLinkedList.prototype.addToHead = function(element) {
    var newNode = new Node(element);
    if (this.head) { 
        this.head.previous = newNode;
        newNode.next = this.head;
    } else {
        this.tail = newNode;
    }
    this.head = newNode;
    this._length++;
};
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