73 lines
3.5 KiB
Markdown
73 lines
3.5 KiB
Markdown
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---
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id: 587d825b367417b2b2512c8c
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title: Implement Heap Sort with a Min Heap
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challengeType: 1
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videoUrl: ''
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localeTitle: 用最小堆实现堆排序
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---
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## Description
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<section id="description">现在我们可以添加和删除元素，让我们看看堆可用于的一些应用程序。堆通常用于实现优先级队列，因为它们始终将最大值或最小值的项存储在第一个位置。此外，它们还用于实现称为堆排序的排序算法。我们将在这里看到如何做到这一点。堆排序使用最小堆，与最大堆相反。最小堆始终将最小值的元素存储在根位置。堆排序通过获取未排序的数组，将数组中的每个项目添加到最小堆中，然后将最小堆中的每个项目提取到新数组中。最小堆结构确保新数组将包含至少最大顺序的原始项。这是最有效的排序算法之一，具有O（nlog（n））的平均和最差情况性能。说明：让我们用最小堆实现堆排序。您可以在此处调整最大堆代码。使用insert，remove和sort方法创建一个MinHeap对象。 sort方法应返回最小堆中从最小到最大排序的所有元素的数组。 </section>
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## Instructions
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<section id="instructions">
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: 存在MinHeap数据结构。
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testString: 'assert((function() { var test = false; if (typeof MinHeap !== "undefined") { test = new MinHeap() }; return (typeof test == "object")})(), "The MinHeap data structure exists.");'
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- text: MinHeap有一个名为insert的方法。
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testString: 'assert((function() { var test = false; if (typeof MinHeap !== "undefined") { test = new MinHeap() } else { return false; }; return (typeof test.insert == "function")})(), "MinHeap has a method called insert.");'
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- text: MinHeap有一个名为remove的方法。
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testString: 'assert((function() { var test = false; if (typeof MinHeap !== "undefined") { test = new MinHeap() } else { return false; }; return (typeof test.remove == "function")})(), "MinHeap has a method called remove.");'
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- text: MinHeap有一个名为sort的方法。
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testString: 'assert((function() { var test = false; if (typeof MinHeap !== "undefined") { test = new MinHeap() } else { return false; }; return (typeof test.sort == "function")})(), "MinHeap has a method called sort.");'
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- text: sort方法返回一个数组，其中包含按排序顺序添加到最小堆的所有项。
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testString: 'assert((function() { var test = false; if (typeof MinHeap !== "undefined") { test = new MinHeap() } else { return false; }; test.insert(3); test.insert(12); test.insert(5); test.insert(10); test.insert(1); test.insert(27); test.insert(42); test.insert(57); test.insert(5); var result = test.sort(); return (isSorted(result)); })(), "The sort method returns an array containing all items added to the min heap in sorted order.");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// check if array is sorted
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function isSorted(arr) {
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var check = (i) => (i == arr.length - 1) ? true : (arr[i] > arr[i + 1]) ? false : check(i + 1);
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return check(0);
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}
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// generate a randomly filled array
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var array = new Array();
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(function createArray(size = 5) {
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array.push(+(Math.random() * 100).toFixed(0));
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return (size > 1) ? createArray(size - 1) : undefined;
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})(25);
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var MinHeap = function() {
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// change code below this line
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// change code above this line
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};
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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