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id	title	challengeType	videoUrl	localeTitle
587d7b7b367417b2b2512b16	Create complex multi-dimensional arrays	1		创建复杂的多维数组

Description

真棒！你刚学了很多关于阵列的知识！这是一个相当高级别的概述，有很多关于使用数组的知识，其中大部分将在后面的章节中看到。但在继续观察对象之前，让我们再看一下，看看阵列如何变得比我们在之前的挑战中看到的更复杂。将数组视为数据结构时，最强大的功能之一是数组可以包含甚至完全由其他数组组成。我们已经看到在之前的挑战中包含数组的数组，但相当简单。但是，数组可以包含无限深度的数组，这些数组可以包含其他数组，每个数组都有自己的任意深度级别，依此类推。通过这种方式，数组可以非常快速地变成非常复杂的数据结构，称为多维或嵌套数组。请考虑以下示例：

让nestedArray = [// top，或first level - 最外面的数组
['deep']，//数组中的数组，2个深度级别
[
['更深']，['更深'] // 2个数组嵌套3层深
]
[
[
['deepest']，['最深'] // 2个数组嵌套了4个级别
]
[
[
['deepest-est？'] //一个数组嵌套5层深
]
]
]
]。

虽然这个例子看似令人费解，但在处理大量数据时，这种复杂程度并非闻所未闻，甚至不同寻常。但是，我们仍然可以使用括号表示法轻松访问此复杂数组的最深层次：

的console.log（nestedArray [2] [1] [0] [0] [0]）;
//日志：最深？

现在我们知道那条数据在哪里，如果需要，我们可以重置它：

nestedArray [2] [1] [0] [0] [0] =“更深”;

的console.log（nestedArray [2] [1] [0] [0] [0]）;
//现在记录：更深入

Instructions

我们已经定义了一个变量myNestedArray ，它等于一个数组。修改myNestedArray ，使用数据元素的字符串，数字和布尔值的任意组合，以便它具有五个深度级别（请记住，最外层的数组是级别1）。某处在第三级上，包括字符串'deep' ，在第四级，包括字符串'deeper' ，并且在第五层上，包括字符串'deepest' 。

Tests

tests:
  - text: <code>myNestedArray</code>应仅包含数字，布尔值和字符串作为数据元素
    testString: 'assert.strictEqual((function(arr) { let flattened = (function flatten(arr) { const flat = [].concat(...arr); return flat.some (Array.isArray) ? flatten(flat) : flat; })(arr); for (let i = 0; i < flattened.length; i++) { if ( typeof flattened[i] !== "number" && typeof flattened[i] !== "string" && typeof flattened[i] !== "boolean") { return false } } return true })(myNestedArray), true, "<code>myNestedArray</code> should contain only numbers, booleans, and strings as data elements");'
  - text: <code>myNestedArray</code>应该有5个级别的深度
    testString: 'assert.strictEqual((function(arr) {let depth = 0;function arrayDepth(array, i, d) { if (Array.isArray(array[i])) {  arrayDepth(array[i], 0, d + 1);} else {  depth = (d > depth) ? d : depth;}if (i < array.length) {  arrayDepth(array, i + 1, d);}  }arrayDepth(arr, 0, 0);return depth;})(myNestedArray), 4, "<code>myNestedArray</code> should have exactly 5 levels of depth");'
  - text: <code>myNestedArray</code>应该在嵌套3级深度的数组中恰好包含一个字符串<code>&quot;deep&quot;</code>
    testString: 'assert((function howDeep(array, target, depth = 0) {return array.reduce((combined, current) => {if (Array.isArray(current)) {  return combined.concat(howDeep(current, target, depth + 1));} else if (current === target) {  return combined.concat(depth);} else {  return combined;}}, []);})(myNestedArray, "deep").length === 1 && (function howDeep(array, target, depth = 0) {return array.reduce((combined, current) => {if (Array.isArray(current)) {  return combined.concat(howDeep(current, target, depth + 1));} else if (current === target) {  return combined.concat(depth);} else {  return combined;}}, []);})(myNestedArray, "deep")[0] === 2, "<code>myNestedArray</code> should contain exactly one occurrence of the string <code>"deep"</code> on an array nested 3 levels deep");'
  - text: <code>myNestedArray</code>应该在嵌套4级深度的数组中恰好包含一个字符串<code>&quot;deeper&quot;</code> deep”
    testString: 'assert((function howDeep(array, target, depth = 0) {return array.reduce((combined, current) => {if (Array.isArray(current)) {  return combined.concat(howDeep(current, target, depth + 1));} else if (current === target) {  return combined.concat(depth);} else {  return combined;}}, []);})(myNestedArray, "deeper").length === 1 && (function howDeep(array, target, depth = 0) {return array.reduce((combined, current) => {if (Array.isArray(current)) {  return combined.concat(howDeep(current, target, depth + 1));} else if (current === target) {  return combined.concat(depth);} else {  return combined;}}, []);})(myNestedArray, "deeper")[0] === 3, "<code>myNestedArray</code> should contain exactly one occurrence of the string <code>"deeper"</code> on an array nested 4 levels deep");'
  - text: <code>myNestedArray</code>应该在嵌套5级深度的数组中恰好包含一个字符串<code>&quot;deepest&quot;</code> <code>myNestedArray</code> <code>&quot;deepest&quot;</code>
    testString: 'assert((function howDeep(array, target, depth = 0) {return array.reduce((combined, current) => {if (Array.isArray(current)) {  return combined.concat(howDeep(current, target, depth + 1));} else if (current === target) {  return combined.concat(depth);} else {  return combined;}}, []);})(myNestedArray, "deepest").length === 1 && (function howDeep(array, target, depth = 0) {return array.reduce((combined, current) => {if (Array.isArray(current)) {  return combined.concat(howDeep(current, target, depth + 1));} else if (current === target) {  return combined.concat(depth);} else {  return combined;}}, []);})(myNestedArray, "deepest")[0] === 4, "<code>myNestedArray</code> should contain exactly one occurrence of the string <code>"deepest"</code> on an array nested 5 levels deep");'

Challenge Seed

let myNestedArray = [
  // change code below this line
  ['unshift', false, 1, 2, 3, 'complex', 'nested'],
  ['loop', 'shift', 6, 7, 1000, 'method'],
  ['concat', false, true, 'spread', 'array'],
  ['mutate', 1327.98, 'splice', 'slice', 'push'],
  ['iterate', 1.3849, 7, '8.4876', 'arbitrary', 'depth']
  // change code above this line
];

Solution

// solution required

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