javascriptNinja/LinkedListsBasicOperations.html at master · amsheehan/javascriptNinja · GitHub

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	<!DOCTYPE html>
<html>
<head>
<title>Basic Linked List Operations</title>
<meta charset="UTF-8">
</head>

<body>
<h2>
      Basic Operations on a Singly-Linked Lists
</h2>

<p>
A Linked List is a collection of Nodes which are <em>linked</em> to each other by references or pointers.
</p>

<p>
A singly-linked list contains Nodes which have a reference or pointer to the Node that follows and some data.
</p>

<p>
Please open the browser's console to see the output.
</p>

<ul id="output"></ul>
<script type="text/javascript">

        //Node Constructor
        function Node(next, data) {
        // Pointer to the next Node.
            this.next = next;
            // Data
            this.data = data;
        }

        // Head of the List.
        var head = null;

        function insertInFront(head, data) {
             var newNode = new Node(null, data);
            // The new Node points to the head of the list.
            newNode.next = head;
            // newNode becomes the head of the list and is returned.
            return newNode;
        }

        function find(head, data) {
             while (head != null && head.data != data) {
                head = head.next;
            }
            if(head == null){
                throw "Could not find the Node containing the given data.";
            }
            else {
            return head;
            }
        }

       function deleteNode(head, data){
           var current = head;
           // Delete head if it contains the given data.
           if (data == head.data) {
               this.head = current.next;
               return true;
           }
           while (current) {
           if(current.next.data == data){
               current.next = current.next.next;
               return true;
           }
           current = current.next;
       }
           return false;
   }

   var first = new Node(null, 20);
   var second = new Node(null, 30);
   var third = new Node(null, 40);
   var fourth = new Node(null, 50);

   first.next = second;
   second.next = third;
   third.next = fourth;
   head = first;

//Tests

   console.log(head);
   head = insertInFront(head, 10);
   console.log(head);
   console.log(head.next);
   console.log(deleteNode(head, 50));
   //The Node referenced by the variable "third" becomes the last node.
   // So third.next should be null.
   console.log(third.next);
   console.log(deleteNode(head, 10));
   console.log(head);
   try {
   console.log(find(head, 30));
   }
   catch (e) {
   console.log(e);
   }

try {
console.log(find(head, 2013));
}
catch (e) {
console.log(e);
}

//Output
//({next:{next:{next:null, data:40}, data:30}, data:20})

//({next:{next:{next:{next:null, data:40}, data:30}, data:20}, data:10})

//({next:{next:{next:null, data:40}, data:30}, data:20})

//true

//null

//true

//({next:{next:{next:null, data:40}, data:30}, data:20})

//({next:{next:null, data:40}, data:30})

//Could not find the Node containing the given data.

    </script>
</body>
</html>