Contents

# Linked List

Implement a doubly linked list.

Like an array, a linked list is a simple linear data structure. Several
common data types can be implemented using linked lists, like queues,
stacks, and associative arrays.

A linked list is a collection of data elements called *nodes*. In a
*singly linked list* each node holds a value and a link to the next node.
In a *doubly linked list* each node also holds a link to the previous
node.

You will write an implementation of a doubly linked list. Implement a
Node to hold a value and pointers to the next and previous nodes. Then
implement a List which holds references to the first and last node and
offers an array-like interface for adding and removing items:

* `push` (*insert value at back*);
* `pop` (*remove value at back*);
* `shift` (*remove value at front*).
* `unshift` (*insert value at front*);

To keep your implementation simple, the tests will not cover error
conditions. Specifically: `pop` or `shift` will never be called on an
empty list.

If you want to know more about linked lists, check [Wikipedia](https://en.wikipedia.org/wiki/Linked_list).

## Setup

Go through the setup instructions for JavaScript to install the
 necessary dependencies:

http://exercism.io/languages/javascript/installation

## Running the test suite

The provided test suite uses [Jasmine](https://jasmine.github.io/).
You can install it by opening a terminal window and running the
following command:

```sh
npm install -g jasmine
```

Run the test suite from the exercise directory with:

```sh
jasmine linked-list.spec.js
```

In many test suites all but the first test have been marked "pending".
Once you get a test passing, activate the next one by changing `xit` to `it`.

## Source

Classic computer science topic

## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.

Version data entries

84 entries across 84 versions & 1 rubygems

Version	Path
trackler-2.2.1.98	tracks/javascript/exercises/linked-list/README.md
trackler-2.2.1.97	tracks/javascript/exercises/linked-list/README.md
trackler-2.2.1.96	tracks/javascript/exercises/linked-list/README.md
trackler-2.2.1.95	tracks/javascript/exercises/linked-list/README.md