fingertree-based-js

Applications of Finger Tree. This project also demostrates usage of Finger Tree in implementing other data structures.

Setup

Using npm:

npm install fingertree-based

API

Sequence

Random access sequence, supports length, push, get and set

init

Create a new Sequence

import { Sequence } from 'fingertree-based';
let seq = new Sequence;

length

Get the length of a sequence

let len = sequence.length;

push(val)

Push a new element of any type into sequence

sequence.push('a');
sequence.push(1);

get(index)

Get element positioned by index, zero-indexed. Minus value is also allowed. It will throw an error if index out of range.

sequence.get(0); // get the first element
sequence.get(-1); // get the last element
sequence.get(1000000); // throws an error if `index` is out of range

set(index, val)

Set element at index. Similar rules with index work like get here.

sequence.set(0, 'hello'); // set the first element
sequence.set(-1, 1); // set the last element
sequence.set(10000, 'error'); // throws an error if `index` is out of range

PriorityQueue

PriorityQueue, supports push and pop.

init

Create a new priority queue.

import { PriorityQueue } from 'fingertree-based';
let queue = new PriorityQueue;

empty

Check if the queue is empty.

let empty = queue.empty; // true or false

push(element, prioriry)

Push an element of any type with priority. priority should be a non-negative integer or an error will be throwed.

queue.push('a', 1);
queue.push(123, 0);
queue.push('error', -1); // throws an error if `priority` is negative

pop()

Pop the element with largest priority. Throws an error if queue is already empty.

let element = queue.pop();