JavaScript Data Structures - Linked List

LinkedList.js

function LinkedList(){
  this.head=null;
  this.tail=null;
}

function Node(value,next,prev){
  this.value=value;
  this.next=next;
  this.prev=prev;
}


LinkedList.prototype.addToHead = function(value){
  var newNode = new Node(value, this.head, null);
  if(this.head) this.head.prev=newNode; 
  else this.tail =newNode;
  this.head = newNode;
  
} 

LinkedList.prototype.addToTail = function(value){
  var newNode = new Node(value, null, this.tail);
  if(this.tail) this.tail.next = newNode;
  else this.head = newNode;
  this.tail = newNode;
}


LinkedList.prototype.removeHead = function(){
  if(!this.head) return null;
  var val = this.head.value;
  this.head = this.head.next;
  if(this.head) this.head.prev = null;
  else this.tail = null;
  return val;
}

LinkedList.prototype.removeTail = function(){
  if(!this.trail) return null;
  var val = this.trail.value;
  this.tail =this.tail.prev;
  if(this.tail) this.tail.next =null;
  else this.head = null;
  return val;
}

LinkedList.prototype.search = function(searchValue){
   var currentNode = this.head;
 
   while(currentNode){
    if(currentNode.value=== searchValue){return currentNode.value;}
    currentNode = currentNode.next;
   }
   return null;
}


LinkedList.prototype.indexOf = function(value){
  var currentNode=this.head;
  var indexes = [];
  var indexNo=0;
  while(currentNode){
    if(currentNode.value===value){
      indexes.push(indexNo);
    }
    currentNode = currentNode.next;
    indexNo++;
  }
  
  return indexes;
  
}




var myLL = new LinkedList();

myLL.addToHead(123);
myLL.addToHead('Deneme');
myLL.addToHead(567);
myLL.addToHead(123);
myLL.addToTail(345345);
myLL.addToTail(433);
myLL.addToTail('Deneme');
myLL.addToTail(433);


//console.log(myLL.indexOf(433));