jsheap

Binary heaps implementation in Javascript

A binary heap is a complete binary tree which satisfies the heap ordering property. The ordering can be one of two types:

• the min-heap property: the value of each node is greater than or equal to the value of its parent, with the minimum-value element at the root.
• the max-heap property: the value of each node is less than or equal to the value of its parent, with the maximum-value element at the root.

A heap is not a sorted structure and can be regarded as partially ordered: there is no particular relationship among nodes on any given level, even among the siblings. It is useful data structure when you need to remove the object with the highest (or lowest) priority. A common use of a heap is to implement a priority queue.

Time complexity

Install

$ npm install --save jsheap

API

HeapTree(params)

Initialises a HeapTree object

• Parameters:
  • params: object with keys 'src' (source array) and 'check' (whether to perform a heapify)

HeapTree.getArray()

Gets the underlying array structure

HeapTree.heapify(arr)

Transform an array into a max-heap

HeapTree.level(i)

Gets the level of a node

HeapTree.parent(i)

Gets the parent of a node

HeapTree.left(i)

Gets the left child of a node

HeapTree.right(i)

Gets the right child of a node

ht.root()

Gets the root of the heap

ht.lastLeaf()

Gets the last leaf of the heap

ht.isEmpty()

Checks whether the heap is empty

ht.bubbleUp(i)

Bubble up a node to its correct position

ht.bubbleDown(i)

Bubble down a node to its correct position

ht.insert(k)

Inserts a node into the heap

ht.deleteRoot()

Deletes the root

ht.delete(i)

Deletes a node from the heap