zhongyangxun zhongyangxun

## shuffle.js
function shuffle(arr) {
  if (!arr || arr.length === 0) {
    return [];
  }

  if (arr.length === 1) {
    return [...arr];
  }

  const map = new Map();

## concurrent-request.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Concurrent request</title>
  </head>
  <body>
    <button id="fetch">fetch</button>

## myRedux.js
function createStore(state, reducer) {
  const listeners = [];

  const getState = () => state;

  const dispatch = (action) => {
    state = reducer(state, action);
    listeners.forEach((item) => item());
  }

## MyPromise.js
// Promise A+: https://promisesaplus.com/

function MyPromise(fn) {
  this.status = 'pending';
  this.value = null;
  this.callbacks = [];

  this.resolve = (newVal) => {
    const fn = () => {
      if (this.status !== 'pending') {

## arr-unique.js
function uniqueWithSet(arr) {
  return Array.from(new Set(arr));
}

function uniqueWithMap(arr) {
  const map = {};
  const res = [];
  for (item of arr) {
    // 主要为了区分数字与字符串，例如数字 1 和字符串 '1'
    const typeSign = typeof item;

## flat.js
const arr = [1, [2, [3], [4]]];
arr.flat(Infinity);

function _flat(arr) {
  return (
    Array.isArray(arr)
      ? arr.reduce((acc, cur) => [...acc, ..._flat(cur)], [])
      : [arr]
  )
}

## myInstanceOf.js
function myInstanceOf(instance, constructor) {
  if (typeof constructor !== 'function') {
    throw Error(`The parameter 'constructor' is not a function!`)
  }

  let proto = instance.__proto__;
  const prototype = constructor.prototype;
  while (proto !== null) {
    if (prototype === proto) {
      return true;

## quickSort.js
function quickSort(list) {
  return sortCore(list, 0, list.length - 1);
}

function sortCore(list, first, last) {
  if (last <= first) {
    return list;
  }
  const povitIndex = partition1(list, first, last);
  // const povitIndex = partition2(list, first, last);

## heapSort.js
function heapSort(arr) {
  for (let i = (arr.length >> 1) - 1; i >= 0; i--) {
    adjust(arr, i, arr.length);
  }

  for (let j = arr.length - 1; j >= 0; j--) {
    swap(arr, 0, j);
    adjust(arr, 0, j);
  }

## deractor.ts
const robot = {
  walk() {
    console.log('walk')
  }
}

robot.walk = (function() {
  const originWalk = robot.walk
  return function() {
    originWalk()
	function shuffle(arr) {
	if (!arr \|\| arr.length === 0) {
	return [];
	}

	if (arr.length === 1) {
	return [...arr];
	}

	const map = new Map();
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8" />
	<meta http-equiv="X-UA-Compatible" content="IE=edge" />
	<meta name="viewport" content="width=device-width, initial-scale=1.0" />
	<title>Concurrent request</title>
	</head>
	<body>
	<button id="fetch">fetch</button>
	function createStore(state, reducer) {
	const listeners = [];

	const getState = () => state;

	const dispatch = (action) => {
	state = reducer(state, action);
	listeners.forEach((item) => item());
	}
	// Promise A+: https://promisesaplus.com/

	function MyPromise(fn) {
	this.status = 'pending';
	this.value = null;
	this.callbacks = [];

	this.resolve = (newVal) => {
	const fn = () => {
	if (this.status !== 'pending') {
	function uniqueWithSet(arr) {
	return Array.from(new Set(arr));
	}

	function uniqueWithMap(arr) {
	const map = {};
	const res = [];
	for (item of arr) {
	// 主要为了区分数字与字符串，例如数字 1 和字符串 '1'
	const typeSign = typeof item;
	const arr = [1, [2, [3], [4]]];
	arr.flat(Infinity);

	function _flat(arr) {
	return (
	Array.isArray(arr)
	? arr.reduce((acc, cur) => [...acc, ..._flat(cur)], [])
	: [arr]
	)
	}
	function myInstanceOf(instance, constructor) {
	if (typeof constructor !== 'function') {
	throw Error(`The parameter 'constructor' is not a function!`)
	}

	let proto = instance.__proto__;
	const prototype = constructor.prototype;
	while (proto !== null) {
	if (prototype === proto) {
	return true;
	function quickSort(list) {
	return sortCore(list, 0, list.length - 1);
	}

	function sortCore(list, first, last) {
	if (last <= first) {
	return list;
	}
	const povitIndex = partition1(list, first, last);
	// const povitIndex = partition2(list, first, last);
	function heapSort(arr) {
	for (let i = (arr.length >> 1) - 1; i >= 0; i--) {
	adjust(arr, i, arr.length);
	}

	for (let j = arr.length - 1; j >= 0; j--) {
	swap(arr, 0, j);
	adjust(arr, 0, j);
	}
	const robot = {
	walk() {
	console.log('walk')
	}
	}

	robot.walk = (function() {
	const originWalk = robot.walk
	return function() {
	originWalk()