ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
167 lines
3.4 KiB
Markdown
167 lines
3.4 KiB
Markdown
---
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id: 587d8250367417b2b2512c60
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title: 创建队列类
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challengeType: 1
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videoUrl: ''
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dashedName: create-a-queue-class
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---
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# --description--
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与堆栈一样，队列是元素的集合。但与堆栈不同，队列遵循FIFO（先入先出）原则。添加到队列的元素将被推送到队列的尾部或末尾，并且只允许删除队列前面的元素。我们可以使用数组来表示队列，但就像堆栈一样，我们希望限制我们对队列的控制量。队列类的两个主要方法是enqueue和dequeue方法。 enqueue方法将元素推送到队列的尾部，dequeue方法移除并返回队列前面的元素。其他有用的方法是front，size和isEmpty方法。说明编写一个将元素推送到队列尾部的入队方法，一个删除并返回前面元素的出列方法，一个让我们看到前面元素的前方法，一个显示长度的大小方法，以及一个isEmpty方法检查队列是否为空。
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# --hints--
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您的`Queue`类应该有一个`enqueue`方法。
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```js
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assert(
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(function () {
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var test = new Queue();
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return typeof test.enqueue === 'function';
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})()
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);
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```
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您的`Queue`类应该有一个`dequeue`方法。
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```js
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assert(
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(function () {
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var test = new Queue();
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return typeof test.dequeue === 'function';
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})()
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);
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```
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您的`Queue`类应该有一个`front`方法。
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```js
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assert(
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(function () {
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var test = new Queue();
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return typeof test.front === 'function';
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})()
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);
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```
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您的`Queue`类应该有一个`size`方法。
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```js
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assert(
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(function () {
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var test = new Queue();
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return typeof test.size === 'function';
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})()
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);
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```
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您的`Queue`类应该有一个`isEmpty`方法。
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```js
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assert(
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(function () {
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var test = new Queue();
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return typeof test.isEmpty === 'function';
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})()
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);
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```
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`dequeue`方法应该删除并返回队列的前端元素
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```js
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assert(
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(function () {
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var test = new Queue();
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test.enqueue('Smith');
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test.enqueue('John');
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return test.dequeue() === 'Smith';
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})()
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);
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```
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`front`方法应该返回队列的front元素的值
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```js
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assert(
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(function () {
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var test = new Queue();
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test.enqueue('Smith');
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test.enqueue('John');
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return test.front() === 'Smith';
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})()
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);
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```
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`size`方法应该返回队列的长度
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```js
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assert(
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(function () {
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var test = new Queue();
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test.enqueue('Smith');
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return test.size() === 1;
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})()
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);
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```
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如果队列中有元素，则`isEmpty`方法应返回`false`
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```js
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assert(
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(function () {
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var test = new Queue();
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test.enqueue('Smith');
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return !test.isEmpty();
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})()
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);
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```
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# --seed--
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## --seed-contents--
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```js
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function Queue() {
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var collection = [];
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this.print = function() {
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console.log(collection);
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};
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// Only change code below this line
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// Only change code above this line
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}
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```
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# --solutions--
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```js
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function Queue () {
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var collection = [];
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this.print = function() {
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console.log(collection);
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};
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// Only change code below this line
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this.enqueue = function(item) {
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collection.push(item);
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}
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this.dequeue = function() {
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return collection.shift();
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}
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this.front = function() {
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return collection[0];
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}
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this.size = function(){
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return collection.length;
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}
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this.isEmpty = function() {
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return collection.length === 0 ? true : false;
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}
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// Only change code above this line
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}
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```
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