lqt0223 lqt0223

## index.js
// 前端收到一个服务器传来的Uint8Array数组后，
//（Uint8Array是JavaScript中的一种带类型的数组（元素为无符号8位整数，取值范围为0-255）
// Uint8Array也是Node.js中Buffer类所采用的数组）

var arr = new Uint8Array(response);
var blob = new Blob(arr.buffer);
img.src = URL.createObjectURL(blob);

## quicksort.js
// 实现基于两种不同原地分区方式的快排
function quicksort(arr){
  qs(arr, 0, arr.length - 1);
}

function qs(arr, start, end){
  if(start < end){
    var k = partition2(arr, start, end);
    qs(arr, start, k);
    qs(arr, k + 1, end);

## heap.js
class Heap {
  constructor() {
    /* A heap is a tree-based data structure with the following features
       - Child nodes for a node in the heap is always greater(or smaller) than
         the parent node(which can be categorized as min-heap or nax-heap)
       - A heap is a complete tree. Because of this feature, we can keep records
         of a heap by array and refer to all nodes by index manipulation
       - For example, in the case of a binary heap where a node has an index of
         i, then its children indexes should be ((i + 1) << 1) - 1 and
         (i + 1) << 1

## index.html
<html>
<head>
  <title></title>
</head>
<body>
<input id="input">

<!-- The DOM that will be binded later -->
<div id="app"></div>

## g.md

      
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                14 Simple algorithm for chromatic aberration effect in JavaScript
              
          
    Chromatic aberration effect - a simple implementation in JavaScript

A chromatic aberration is an optical effect caused by one or more color channels being displaced. Although it is an optical failure and should be avoided for displaying or image capturing devices, chromatic aberration can be used to make graphics be more realistic in some other applications like 3D games.
The following codes is an example of implementing the effect using ImageData API of HTML5 canvas. By fetching and manipulating pixel data of the image, the chromatic aberration effect is easy to achieve.
<html>
<body>
<canvas id="canvas"></canvas>

  
## graph.js
// unweighted undirectional graph implementation
// TODO directional and weighted graph implementation; travelling salesman's problem

class Graph {
  constructor() {
    this.vertices = [];
    this.edges = [];
  }

  add(){

## p&c.js
/*

Permutation in mathmatics stands for all possible order for a set.
Combination in mathmatics stands for all possible ways of selecting items from a set.
Find more at
https://en.wikipedia.org/wiki/Permutation
https://en.wikipedia.org/wiki/Combination

*/

## deepcopy.js
// You are welcome to have a test on this function to check if it supports deep copy for very complex nested objects.
function deepCopy(o){
  if(typeof o === "object" && o !== null){
    var _o = new o.constructor();
    for(var k in o){
      _o[k] = deepCopy(o[k]);
    }
    return _o;
  }else{
    return o;

## graph.js
// Weighted directional graph implementation and Dijkstra's algorithm

class Graph {

  constructor() {
    this.vertices = [];
    this.edges = [];
  }

  // add a sequence of vertices to the graph

## bitwise.js
// bitwise operation and utilities

// Left shift by 1, will multiply the number by 2
console.log(2 << 1); // return 4

// Right shift by 1, will divide the number by 2.
// In JavaScript, the decimal part will be floored
console.log(2 >> 1); // return 1
console.log(3 >> 1); // return 1
	// 前端收到一个服务器传来的Uint8Array数组后，
	//（Uint8Array是JavaScript中的一种带类型的数组（元素为无符号8位整数，取值范围为0-255）
	// Uint8Array也是Node.js中Buffer类所采用的数组）

	var arr = new Uint8Array(response);
	var blob = new Blob(arr.buffer);
	img.src = URL.createObjectURL(blob);
	// 实现基于两种不同原地分区方式的快排
	function quicksort(arr){
	qs(arr, 0, arr.length - 1);
	}

	function qs(arr, start, end){
	if(start < end){
	var k = partition2(arr, start, end);
	qs(arr, start, k);
	qs(arr, k + 1, end);
	class Heap {
	constructor() {
	/* A heap is a tree-based data structure with the following features
	- Child nodes for a node in the heap is always greater(or smaller) than
	the parent node(which can be categorized as min-heap or nax-heap)
	- A heap is a complete tree. Because of this feature, we can keep records
	of a heap by array and refer to all nodes by index manipulation
	- For example, in the case of a binary heap where a node has an index of
	i, then its children indexes should be ((i + 1) << 1) - 1 and
	(i + 1) << 1
	<html>
	<head>
	<title></title>
	</head>
	<body>
	<input id="input">

	<!-- The DOM that will be binded later -->
	<div id="app"></div>
	// unweighted undirectional graph implementation
	// TODO directional and weighted graph implementation; travelling salesman's problem

	class Graph {
	constructor() {
	this.vertices = [];
	this.edges = [];
	}

	add(){
	/*

	Permutation in mathmatics stands for all possible order for a set.
	Combination in mathmatics stands for all possible ways of selecting items from a set.
	Find more at
	https://en.wikipedia.org/wiki/Permutation
	https://en.wikipedia.org/wiki/Combination

	*/
	// You are welcome to have a test on this function to check if it supports deep copy for very complex nested objects.
	function deepCopy(o){
	if(typeof o === "object" && o !== null){
	var _o = new o.constructor();
	for(var k in o){
	_o[k] = deepCopy(o[k]);
	}
	return _o;
	}else{
	return o;
	// Weighted directional graph implementation and Dijkstra's algorithm

	class Graph {

	constructor() {
	this.vertices = [];
	this.edges = [];
	}

	// add a sequence of vertices to the graph
	// bitwise operation and utilities

	// Left shift by 1, will multiply the number by 2
	console.log(2 << 1); // return 4

	// Right shift by 1, will divide the number by 2.
	// In JavaScript, the decimal part will be floored
	console.log(2 >> 1); // return 1
	console.log(3 >> 1); // return 1