Mheap

🌳 Binary min & max heaps for ES6

Description

ES6 implementation of the binary min & max heap data structures with TypeScript support.

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Contents

- Description
- Install
- In Depth
- Usage
- API
- Development
- Related
- Team
- License

Install

$3

``bash
yarn add mheap
`

$3

`bash
npm install mheap
`

In Depth

A binary heap is a heap data structure that takes the form of a binary tree, defined with two additional constraints:

- Shape property: A binary heap is a complete binary tree, that is all levels, except possibly the last one / deepest are fully filled, and if the last level of the tree is not complete, the nodes of that level are filled from left to right.

- Heap property: The key stored in each node is either greater than or equal to or less than or equal to the keys in the node's children, according to the maximum & minimum total orders, respectively.

Heaps, where the parent key is greater than or equal to the child keys are called max-heaps, and those where it is less than or equal to are called min-heaps.

Mheap binary min & max heaps are internally implemented with an array, where nodes are stored by the level order traversal of the heap and the root node is always placed at index 0. This is due to the fact that any binary tree can be stored in an array, but because a binary heap is always a complete binary tree, it can be compactly & uniquely represented by storing its level order traversal in an array. As a result, no space is required for pointers, instead, the parent and children of each node are found by arithmetic calculations on array indices.

Usage

Mheap exposes a chainable API, that can be utilized through a simple and minimal syntax, allowing you to combine methods effectively.

Usage examples can be also found at the test directory.

`js
'use strict';
const {MaxHeap, MinHeap, Node} = require('mheap');

const maxHeap = new MaxHeap();
//=> MaxHeap { data: [] }

maxHeap.insert(15, 'A');
//=> MaxHeap { data: [Node { key: 15, value: 'A' }] }

maxHeap.root;
//=> Node { key: 15, value: 'A' }

const node = new Node(15, 'A');

maxHeap.root.toPair();
//=> [15, 'A']

maxHeap.root.key === node.key;
//=> true

maxHeap.root.value === node.value;
//=> true

maxHeap.insert(10, 'B').insert(5, 'C');
//=> MaxHeap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' } ] }

maxHeap.left(0);
//=> Node { key: 10, value: 'B' }

maxHeap.right(0);
//=> Node { key: 5, value: 'C' }

maxHeap.insert(7, 'D').insert(8, 'E').insert(2, 'F');
//=> MaxHeap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' },}
// Node { key: 7, value: 'D' },
// Node { key: 8, value: 'E' },
// Node { key: 2, value: 'F' } ] }

maxHeap.search(8);
//=> Node { key: 8, value: 'E',

maxHeap.includes(2);
//=> true

maxHeap.includes(100);
//=> false

maxHeap.height();
//=> 2

maxHeap.indexOf(7);
//=> 3

maxHeap.remove(1);
//=> MaxHeap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 8, value: 'E' },
// Node { key: 5, value: 'C' },
// Node { key: 7, value: 'D' },
// Node { key: 2, value: 'F' } ] }

maxHeap.children(0);
//=> { left: Node { key: 8, value: 'E' },
// right: Node { key: 5, value: 'C' } }

maxHeap.extractMax();
//=> Node { key: 15, value: 'A' }

maxHeap.toPairs();
//=> [ [ 8, 'E' ], [ 7, 'D' ], [ 5, 'C' ], [ 2, 'F' ] ]
`

API

The following documentation holds for both binary max & min heaps. The below described heap instance is used to depict the same methods that are available to both a min and a max heap, without overlooking their above described differences and unique qualities. For dedicated methods to min or max binary heaps, the min & max instances are used respectively.

#### heap.root

- Return Type: Node | undefined

Returns the root node of the heap.
If the heap is empty undefined is returned.

`js
heap.insert(10, 'A');
heap.root;
// => Node { key: 10, value: 'A' }
`

#### heap.size

- Return Type: Number

Returns the total number of nodes residing in the heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.size;
// => 3
`

#### heap.childIndices(index)

- Return Type: { left?: Number, right?: Number }

Returns an object containing the child indices of the parent node corresponding to the given index. Both the given parent index and the returned child indices are relative to the unique level order array representation of the heap. If the parent node is either a full, a partial or leaf node then the returned object will respectively contain both, only one or none of the child indices.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.childIndices(0);
// => { left: 1, right: 2 }
heap.childIndices(1);
// => { }
heap.childIndices(2);
// => { }
`

#### heap.children(index)

- Return Type: { left?: Node, right?: Node }

Returns an object containing the children of the parent node corresponding to the given index. If the parent node is either a full, a partial or leaf node then the returned object will respectively contain both, only one or none of the child nodes.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.children(0);
// => { left: Node { key:10, value 'B' }, right: Node { key: 5, value 'C' } }
heap.children(1);
// => { }
heap.children(2);
// => { }
`

#### heap.clear()

- Return Type: Heap

Mutates the heap by removing all residing nodes and returns it empty.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
//=> Heap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' } ] }
heap.size;
//=> 3
heap.clear();
//=> Heap { data: [] } }
heap.size;
//=> 0
`

#### node.degree(index)

- Return Type: Number

Returns the number of sub-heaps that the node, corresponding to the give index, points to.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.degree(0);
//=> 2
heap.degree(1);
//=> 0
`

#### heap.extract(index)

- Return Type: Node | undefined

Mutates the binary heap by removing the node, corresponding to the given index, and properly readjusts the heap in order for it to fulfill the two shape & heap properties. Returns the removed node, if the node is found, or undefined if it is not.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D').insert(7, 'E').insert(1, 'F');
//=> Heap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' },
// Node { key: 8, value: 'D' },
// Node { key: 7, value: 'E' },
// Node { key: 1, value: 'F' } ] }
heap.extract(1);
//=> Node { key: 10, value: 'B' }
heap;
//=> Heap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 8, value: 'D' },
// Node { key: 5, value: 'C' },
// Node { key: 1, value: 'F' },
// Node { key: 7, value: 'E' } ] }
`

#### maxHeap.extractMax()

- Return Type: Node | undefined

Mutates the binary max heap by removing the node with the greatest key, known as maximum node / root node, and properly readjusts the max heap in order for it to fulfill the two shape & heap properties. Returns the maximum node, if the heap is not empty, or undefined if it is.

`js
maxHeap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D').insert(7, 'E').insert(1, 'F');
//=> MaxHeap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' },
// Node { key: 8, value: 'D' },
// Node { key: 7, value: 'E' },
// Node { key: 1, value: 'F' } ] }
maxHeap.extractMax();
//=> Node { key: 15, value: 'A' }
heap;
//=> MaxHeap { data: [
// Node { key: 10, value: 'B' },
// Node { key: 8, value: 'D' },
// Node { key: 5, value: 'C' },
// Node { key: 1, value: 'F' },
// Node { key: 7, value: 'E' } ] }
`

#### minHeap.extractMin()

- Return Type: Node | undefined

Mutates the binary min heap by removing the node with the smallest key, known as minimum node / root node, and properly readjusts the min heap in order for it to fulfill the two shape & heap properties. Returns the minimum node, if the heap is not empty, or undefined if it is.

`js
minHeap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D').insert(7, 'E').insert(1, 'F');
//=> MinHeap { data: [
// Node { key: 1, value: 'F' },
// Node { key: 7, value: 'E' },
// Node { key: 5, value: 'C' },
// Node { key: 15, value: 'A' },
// Node { key: 8, value: 'D' },
// Node { key: 10, value: 'B' } ] }
minHeap.extractMin();
//=> Node { key: 1, value: 'F' }
heap;
//=> MinHeap { data: [
// Node { key: 5, value: 'C' },
// Node { key: 7, value: 'E' },
// Node { key: 10, value: 'B' },
// Node { key: 15, value: 'A' },
// Node { key: 8, value: 'D' } ] }
`

#### heap.fullNodes()

- Return Type: Array

Applies level order traversal to the heap and stores each traversed full node (node with two non-null children) in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.fullNodes();
//=> [
// Node { key: 15, value: 'A' }
// ]
`

#### heap.height()

- Return Type: Number

Returns the maximum distance of any leaf node from the root.
If the heap is empty -1 is returned.

`js
heap.insert(15, 'A');
heap.height();
// => 0
heap.insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.height();
//=> 2
`

#### heap.includes(key)

- Return Type: Boolean

Determines whether the heap includes a node with a certain key, returning true or false as appropriate.

##### key

- Type: Number

Node key to search for.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.includes(10);
// => true
heap.includes(25);
// => false
heap.includes(5);
// => true
`

#### heap.indexOf(key)

- Return Type: Number

Returns the first index at which the node with the given key can be found in the unique level order array representation of the heap. If the node is not present then -1 is returned.

##### key

- Type: Number

Node key to search for.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C');
heap.indexOf(10);
// => 1
heap.indexOf(25);
// => -1
heap.indexOf(5);
// => 2
`

#### heap.insert(key, value)

- Return Type: Heap

Mutates the heap by inserting a new node at the appropriate location and return the heap itself.

##### key

- Type: Number

Can be any number that will correspond to the key of the created node.

##### value

- Type: Any

Can be any value that will stored in the new node.

`js
heap.insert(15, 'A');
//=> Heap { data: [ Node { key: 15, value: 'A' } ] }
heap.insert(10, 'B').insert(5, 'C');
//=> Heap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' } ] }
`

#### heap.internalNodes()

- Return Type: Array

Applies level order traversal to the heap and stores each traversed internal node (non-leaf nodes) in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.fullNodes();
//=> [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' }
// ]
`

#### heap.isEmpty()

- Return Type: Boolean

Determines whether the heap is empty, returning true or false as appropriate.

`js
heap.insert(10, 'A');
heap.isEmpty();
//=> false
heap.clear().isEmpty();
//=> true
`

#### heap.isFullNode(index)

- Return Type: Boolean

Determines whether the node, corresponding to the given index, is a full node (has two non-null children), returning true or false as appropriate.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A');
heap.isFullNode(0)
//=> false
heap.insert(10, 'B').insert(5, 'C').isFullNode(0);
//=> true
`

#### heap.isInternalNode(index)

- Return Type: Boolean

Determines whether the node, corresponding to the given index, is an internal node (has at least one non-null child), returning true or false as appropriate.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(10, 'A').isInternalNode(0);
//=> false
heap.insert(5, 'B').isInternalNode(0);
//=> true
`

#### heap.isLeafNode(index)

- Return Type: Boolean

Determines whether the node, corresponding to the given index, is a leaf node (has no children), returning true or false as appropriate.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').isLeafNode(0);
//=> true
heap.insert(10, 'B').isLeafNode(0);
//=> false
`

#### heap.isPartialNode(index)

- Return Type: Boolean

Determines whether the node, corresponding to the given index, is a partial node (has ony one non-null child), returning true or false as appropriate.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').isPartialNode(0);
//=> false
heap.insert(10, 'B').isPartialNode(0);
//=> true
heap.insert(5, 'C').isPartialNode(0);
//=> false
`

#### heap.keys()

- Return Type: Array

Applies level order traversal to the heap and stores the key of each traversed node in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
//=> [ 15, 10, 5, 8 ]
`

#### heap.leafNodes()

- Return Type: Array

Applies level order traversal to the heap and stores each traversed leaf node (node without children) in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.leafNodes();
//=> [
// Node { key: 5, value: 'C' },
// Node { key: 8, value: 'D' }
// ]
`

#### heap.left(index)

- Return Type: Node | undefined

Returns the left child of the parent node corresponding to the given index.
If the left child does not exist then undefined is returned.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.left(0);
//=> Node { key: 5, value: 'C' }
heap.left(1);
//=> Node { key: 8, value: 'D' }
heap.left(2);
//=> undefined
`

#### heap.leftIndex(index)

- Return Type: Number

Returns the index of left child, which is equal to 2 * index + 1, of the parent node corresponding to the given index. Both the given parent index and the returned left child index are relative to the unique level order array representation of the heap.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.leftIndex(0);
//=> 1
heap.leftIndex(1);
//=> 3
heap.leftIndex(2);
//=> 5
`

#### heap.levelOrder(fn)

- Return Type: Heap

Applies level-order traversal (breadth-first traversal) to the heap and executes the provided fn function on each traversed node without mutating the heap. Returns the heap itself at the end of the traversal.

##### fn

- Type: Function

Unary function to execute on each node.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.levelOrder(node => console.log(node.key));
//=> 15
//=> 10
//=> 5
//=> 8
`

#### heap.maxChild(index)

- Return Type: Node | undefined

Returns the child, with the greatest key value, of the parent node corresponding to the given index. If the parent node is either a partial or a leaf node then the method respectively returns the only child node or undefined.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.maxChild(0);
//=> Node { key: 10, value: 'B' }
heap.maxChild(1);
//=> Node { key: 8, value: 'D' }
heap.maxChild(2);
//=> undefined
`

#### heap.maxChildIndex(index)

- Return Type: Number

Returns the index of the child, with the greatest key value, of the parent node corresponding to the given index. Both the given parent index and the returned max child index are relative to the unique level order array representation of the heap. If the parent node is either a partial or leaf node then the method respectively returns the index of the only child node or -1.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.maxChildIndex(0);
//=> 1
heap.maxChildIndex(1);
//=> 3
heap.maxChildIndex(2);
//=> -1
`

#### heap.minChild(index)

- Return Type: Node | undefined

Returns the child, with the smallest key value, of the parent node corresponding to the given index. If the parent node is either a partial or a leaf node then the method respectively returns the only child node or undefined.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.minChild(0);
//=> Node { key: 5, value: 'C' }
heap.minChild(1);
//=> Node { key: 8, value: 'D' }
heap.minChild(2);
//=> undefined
`

#### heap.minChildIndex(index)

- Return Type: Number

Returns the index of the child, with the smallest key value, of the parent node corresponding to the given index. Both the given parent index and the returned min child index are relative to the unique level order array representation of the heap. If the parent node is either a partial or leaf node then the method respectively returns the index of the only child node or -1.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.maxChildIndex(0);
//=> 2
heap.maxChildIndex(1);
//=> 3
heap.maxChildIndex(2);
//=> -1
`

#### heap.node(index)

- Return Type: Node | undefined

Returns the the node corresponding to the give index. If the node does not exist then undefined is returned.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.node(0);
//=> Node { key: 15, value: 'A' }
heap.node(2);
//=> Node { key: 5, value: 'C' }
heap.node(15);
//=> undefined
`

#### heap.parent(index)

- Return Type: Node | undefined

Returns the parent node of the node corresponding to the given index.
If the parent node does not exist then undefined is returned.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.parent(0);
//=> undefined
heap.parent(1);
//=> Node { key: 15, value: 'A' }
heap.parent(3);
//=> Node { key: 10, value: 'B' }
`

#### heap.parentIndex(index)

- Return Type: Number

Returns the index of the parent node, which is equal to floor((index - 1) / 2), of the node corresponding to the given index. Both the given node index and the returned parent index are relative to the unique level order array representation of the heap.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.parentIndex(0);
//=> -1
heap.parentIndex(1);
//=> 0
heap.parentIndex(3);
//=> 1
`

#### heap.partialNodes()

- Return Type: Array

Applies level order traversal to the heap and stores each traversed partial node (node only one non-null child) in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.partialNodes();
//=> [
// Node { key: 10, value: 'B' }
// ]
`

#### heap.remove(index)

- Return Type: Heap

Mutates the binary heap by removing the node, corresponding to the given index, and properly readjusts the heap in order for it to fulfill the two shape & heap properties. Returns the heap itself.

##### index

- Type: Number

Node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D').insert(7, 'E').insert(1, 'F');
//=> Heap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' },
// Node { key: 8, value: 'D' },
// Node { key: 7, value: 'E' },
// Node { key: 1, value: 'F' } ] }
heap.remove(0);
//=> Heap { data: [
// Node { key: 10,value: 'B' },
// Node { key: 8, value: 'D' },
// Node { key: 5, value: 'C' },
// Node { key: 1, value: 'F' },
// Node { key: 7, value: 'E' } ] }
`

#### heap.right(index)

- Return Type: Node | undefined

Returns the right child node of the parent node corresponding to the given index.
If the right child node does not exist then undefined is returned.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.right(0);
//=> Node { key: 5, value: 'C' }
heap.right(1);
//=> undefined
`

#### heap.rightIndex(index)

- Return Type: rightIndex

Returns the index of the right child node, which is equal to 2 * index + 2;, of the parent node corresponding to the given index. Both the given parent node index and the returned right child index are relative to the unique level order array representation of the heap.

##### index

- Type: Number

Parent node index relative to the unique level order array representation of the binary heap.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.rightIndex(0);
//=> 2
heap.rightIndex(1);
//=> 4
heap.rightIndex(2);
//=> 6
`

#### heap.search(key)

- Return Type: Node | undefined

Determines whether the heap includes a node with a certain key, returning the targeted node or undefined as appropriate.

##### key

- Type: Number

Node key to search for.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.search(10);
// => Node { key: 10, value: 'B' }
heap.search(5);
// => Node { key: 5, value: 'C' }
heap.search(25);
// => undefined
`

#### heap.toArray()

- Return Type: Array

Applies level order traversal to the heap and stores each traversed node in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.toArray();
//=> [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'B' },
// Node { key: 5, value: 'C' },
// Node { key: 8, value: 'D' }
// ]
`

#### heap.toPairs()

- Return Type: Array<[Number, Any]>

Applies level order traversal to the heap and for each traversed node stores in an array an ordered-pair/2-tuple, where the first element is a number corresponding to the key of the traversed node, and the last one is a value of type any, corresponding to the value stored in the traversed node.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
heap.toPairs();
//=> [ [ 15, 'A' ], [ 10, 'B' ], [ 5, 'C' ], [ 8, 'D' ] ]
`

#### heap.update(key, value)

- Return Type: Heap

Mutates the heap by inserting a new value at the new node corresponding to the given key.
Returns the heap itself.

##### key

- Type: Number

The number corresponding to the key of the existing node.

##### value

- Type: Any

The new value that will be stored in the existing node.

`js
heap.insert(15, 'A').insert(10, 'B')
//=> Heap { data: [
// Node { key: 15, value: 'A' },
// Node { key: 10, value: 'A' } ] }
heap.update(10, 'a').insert(10, 'b');
//=> Heap { data: [
// Node { key: 15, value: 'a' },
// Node { key: 10, value: 'b' } ] }
`

#### heap.values()

- Return Type: Array

Applies level order traversal to the heap and stores the value of each traversed node in an array.
The array is returned at the end of the traversal.

`js
heap.insert(15, 'A').insert(10, 'B').insert(5, 'C').insert(8, 'D');
//=> [ 'A', 'B', 'C', 'D' ]
`

Also available, along with the MaxHeap & MinHeap exposed classes, is the Node class, mainly useful for testing purposes, since it can be utilized to compare heap nodes. The class has a binary constructor method, with a key and a value parameter, corresponding to the key and the value stored in the created instance, respectively.

#### node.key

- Return Type: Number

The key corresponding to the node instance.

`js
const {Node} = require('mheap');

const node = new Node(10, 'A');
// => Node { key:10, value: 'A' }
node.key;
//=> 10
`

#### node.value

- Return Type: Any

The value that the node contains.

`js
const {Node} = require('mheap');

const node = new Node(10, 'A');
// => Node { key: 10, value: 'A' }
node.value;
//=> 'A'
node.value = 'B'
// => Node { key: 10, value: 'B' }
`

#### node.toPair()

- Return Type: [Number, Any]

Returns an ordered-pair/2-tuple, where the first element is a number corresponding to the key of the node, and the last one is a value, that can be of any type, corresponding to the value stored in the node.

`js
const {Node} = require('mheap');


const node = new Node(5, 'B');

node.toPair();
//=> [ 5, 'B' ]
`

Development

For more info on how to contribute to the project, please read the contributing guidelines.

- Fork the repository and clone it to your machine
- Navigate to your local fork: cd mheap
- Install the project dependencies: npm install or yarn install
- Lint the code and run the tests: npm test or yarn test`

Related

- binstree - Binary search trees for ES6
- doublie - Doubly circular & linear linked lists for ES6
- singlie - Singly circular & linear linked lists for ES6

Team

- Klaus Sinani (@klaussinani)

License

MIT