ts-fibonacci-heap

A TypeScript implementation of the Fibonacci heap data structure.

Note that the primary purpose of this library is education but it should work in a production environment as well. It's certainly not as performant as it could be as it optimises for readability, abstraction and safety over raw performance.

Features

• 100% test coverage
• Supports all common heap operations
• Store keys with optional associated values
• Optional custom compare function that can utilize both key and value to give full control over the order of the data

Install

npm install --save @tyriar/fibonacci-heap

Usage

See the typings file for the full API.

// Import npm module
import { FibonacciHeap } from '@tyriar/fibonacci-heap';

// Construct FibonacciHeap
const heap = new FibonacciHeap<number, any>();
// Insert keys only
heap.insert(3);
heap.insert(7);
// Insert keys and values
heap.insert(8, {foo: 'bar'});
heap.insert(1, {foo: 'baz'});

// Extract all nodes in order
while (!heap.isEmpty()) {
  const node = heap.extractMinimum();
  console.log('key: ' + node.key + ', value: ' + node.value);
}
// > key: 1, value: [object Object]
// > key: 3, value: undefined
// > key: 7, value: undefined
// > key: 8, value: [object Object]

// Construct custom compare FibonacciHeap
const heap2 = new FibonacciHeap<string, string>(function (a, b) {
  return (a.key + a.value).localeCompare(b.key + b.value);
});
heap2.insert('2', 'B');
heap2.insert('1', 'a');
heap2.insert('1', 'A');
heap2.insert('2', 'b');

// Extract all nodes in order
while (!heap2.isEmpty()) {
  const node = heap2.extractMinimum();
  console.log('key: ' + node.key + ', value: ' + node.value);
}
// > key: 1, value: a
// > key: 1, value: A
// > key: 2, value: b
// > key: 2, value: B

Operation time complexity

Operation	Complexity
clear	Θ(1)*
decreaseKey	Θ(1)*
delete	O(log n)*
extractMinimum	O(log n)*
findMinimum	Θ(1)
insert	Θ(1)
isEmpty	Θ(1)
size	Θ(n)
union	Θ(1)

* amortized