107 lines
2.9 KiB
Markdown
107 lines
2.9 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244c6
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title: Stand in Line
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challengeType: 1
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videoUrl: ''
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localeTitle: 站在队中
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---
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## Description
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<section id="description">在计算机科学中， <dfn>队列</dfn>是一个抽象的<dfn>数据结构</dfn> ，其中项目按顺序保存。可以在<code>queue</code>的后面添加新项目，并从<code>queue</code>的前面取出旧项目。编写一个函数<code>nextInLine</code> ，它接受一个数组（ <code>arr</code> ）和一个数字（ <code>item</code> ）作为参数。将数字添加到数组的末尾，然后删除数组的第一个元素。然后， <code>nextInLine</code>函数应返回已删除的元素。 </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: '<code>nextInLine([], 5)</code>应返回一个数字。'
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testString: 'assert.isNumber(nextInLine([],5), "<code>nextInLine([], 5)</code> should return a number.");'
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- text: '<code>nextInLine([], 1)</code>应该返回<code>1</code>'
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testString: 'assert(nextInLine([],1) === 1, "<code>nextInLine([], 1)</code> should return <code>1</code>");'
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- text: '<code>nextInLine([2], 1)</code>应返回<code>2</code>'
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testString: 'assert(nextInLine([2],1) === 2, "<code>nextInLine([2], 1)</code> should return <code>2</code>");'
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- text: '<code>nextInLine([5,6,7,8,9], 1)</code>应该返回<code>5</code>'
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testString: 'assert(nextInLine([5,6,7,8,9],1) === 5, "<code>nextInLine([5,6,7,8,9], 1)</code> should return <code>5</code>");'
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- text: '在<code>nextInLine(testArr, 10)</code> ， <code>testArr[4]</code>应为<code>10</code>'
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testString: 'nextInLine(testArr, 10); assert(testArr[4] === 10, "After <code>nextInLine(testArr, 10)</code>, <code>testArr[4]</code> should be <code>10</code>");'
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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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function nextInLine(arr, item) {
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// Your code here
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return item; // Change this line
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}
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// Test Setup
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var testArr = [1,2,3,4,5];
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// Display Code
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console.log("Before: " + JSON.stringify(testArr));
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console.log(nextInLine(testArr, 6)); // Modify this line to test
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console.log("After: " + JSON.stringify(testArr));
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```
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</div>
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### Before Test
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<div id='js-setup'>
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```js
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var logOutput = [];
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var originalConsole = console
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function capture() {
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var nativeLog = console.log;
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console.log = function (message) {
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logOutput.push(message);
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if(nativeLog.apply) {
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nativeLog.apply(originalConsole, arguments);
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} else {
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var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
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nativeLog(nativeMsg);
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}
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};
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}
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function uncapture() {
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console.log = originalConsole.log;
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}
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capture();
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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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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