78 lines
1.2 KiB
Markdown
78 lines
1.2 KiB
Markdown
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---
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title: Y combinator
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id: 594810f028c0303b75339ad5
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challengeType: 5
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videoUrl: ''
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localeTitle: ''
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---
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## Description
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undefined
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## Instructions
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undefined
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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: ''
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testString: 'assert.equal(typeof Y(f => n => n), "function", "Y must return a function");'
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- text: ''
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testString: 'assert.equal(factorial(1), 1, "factorial(1) must return 1.");'
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- text: ''
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testString: 'assert.equal(factorial(2), 2, "factorial(2) must return 2.");'
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- text: ''
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testString: 'assert.equal(factorial(3), 6, "factorial(3) must return 6.");'
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- text: ''
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testString: 'assert.equal(factorial(4), 24, "factorial(4) must return 24.");'
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- text: ''
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testString: 'assert.equal(factorial(10), 3628800, "factorial(10) must return 3628800.");'
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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 Y(f) {
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return function() {
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// Good luck!
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};
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}
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var factorial = Y(function(f) {
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return function (n) {
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return n > 1 ? n * f(n - 1) : 1;
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};
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});
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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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