linkedList.js

/** Node in the linked list **/
function Node(element) {  
    // Data in the node
    this.element = element;  
    // Pointer to the next node 
    this.next = null;
}
    function LinkedList() {  
        var length = 0;  
        var head = null;  
        this.size = function () {    
            return length;  
        }  
        this.head = function () {    
            return head;  
        }  
        this.add = function (element) {    
            var node = new Node(element);    
            if (head == null) {      
                head = node;    
            } else {      
                var currentNode = head;      
                while (currentNode.next) {        
                    currentNode = currentNode.next;      
                }      
                currentNode.next = node;    
            }    
            length++;  
        }  
        this.remove = function (element) {    
            var currentNode = head;    
            var previousNode;    
            if (currentNode.element === element) {      
                head = currentNode.next;    
            } else {      
                while (currentNode.element !== element) {        
                    previousNode = currentNode;        
                    currentNode = currentNode.next;      
                }      
                previousNode.next = currentNode.next;    
            }    
            length--;  
        }  
        this.isEmpty = function () {    
            return length === 0;  
        }  
        this.indexOf = function (element) {    
            var currentNode = head;    
            var index = -1;    
            while (currentNode) {      
                index++;      
                if (currentNode.element === element) {        
                    return index;      
                }      
                currentNode = currentNode.next;    
            }    
            return -1;  
        }  
        this.elementAt = function (index) {    
            var currentNode = head;    
            var count = 0;    
            while (count < index) {      
                count++;      
                currentNode = currentNode.next;    
            }    
            return currentNode.element;  
        }  
        this.addAt = function (index, element) {    
            var node = new Node(element);    
            var currentNode = head;    
            var previousNode;    
            var currentIndex = 0;    
            if (index > length) {      
                return false;    
            }    
            if (index === 0) {      
                node.next = currentNode;      
                head = node;    
            } else {      
                while (currentIndex < index) {        
                    currentIndex++;        
                    previousNode = currentNode;        
                    currentNode = currentNode.next;      
                }      
                node.next = currentNode;      
                previousNode.next = node;    
            }    
            length++;  
        }  
        this.removeAt = function (index) {    
            var currentNode = head;    
            var previousNode;    
            var currentIndex = 0;    
            if (index < 0 || index >= length) {      
                return null;    
            }    
            if (index === 0) {      
                head = currentIndex.next;    
            } else {      
                while (currentIndex < index) {        
                    currentIndex++;        
                    previousNode = currentNode;        
                    currentNode = currentNode.next;      
                }      
                previousNode.next = currentNode.next;    
            }    
            length--;    
            return currentNode.element;  
        }
    }