6cfd0fc503
* fix: improve Project Euler descriptions and test case Improve formatting of Project Euler test descriptions. Also add poker hands array and new test case for problem 54 * feat: add typeof tests and gave functions proper names for first 100 challenges * fix: continue fixing test descriptions and adding "before test" sections * fix: address review comments * fix: adjust grids in 18 and 67 and fix some text that reference files rather than the given arrays * fix: implement bug fixes and improvements from review * fix: remove console.log statements from seed and solution
84 lines
1.8 KiB
Markdown
84 lines
1.8 KiB
Markdown
---
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id: 5900f36f1000cf542c50fe82
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challengeType: 5
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title: 'Problem 3: Largest prime factor'
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forumTopicId: 301952
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---
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## Description
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<section id='description'>
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The prime factors of 13195 are 5, 7, 13 and 29.
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What is the largest prime factor of the given `number`?
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</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>largestPrimeFactor(2)</code> should return a number.
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testString: assert(typeof largestPrimeFactor(2) === 'number');
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- text: <code>largestPrimeFactor(2)</code> should return 2.
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testString: assert.strictEqual(largestPrimeFactor(2), 2);
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- text: <code>largestPrimeFactor(3)</code> should return 3.
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testString: assert.strictEqual(largestPrimeFactor(3), 3);
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- text: <code>largestPrimeFactor(5)</code> should return 5.
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testString: assert.strictEqual(largestPrimeFactor(5), 5);
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- text: <code>largestPrimeFactor(7)</code> should return 7.
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testString: assert.strictEqual(largestPrimeFactor(7), 7);
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- text: <code>largestPrimeFactor(13195)</code> should return 29.
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testString: assert.strictEqual(largestPrimeFactor(13195), 29);
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- text: <code>largestPrimeFactor(600851475143)</code> should return 6857.
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testString: assert.strictEqual(largestPrimeFactor(600851475143), 6857);
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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 largestPrimeFactor(number) {
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// Good luck!
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return true;
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}
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largestPrimeFactor(13195);
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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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const largestPrimeFactor = (number)=>{
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let largestFactor = number;
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for(let i = 2;i<largestFactor;i++){
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if(!(largestFactor%i)){
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largestFactor = largestFactor/i;
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largestPrimeFactor(largestFactor);
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}
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}
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return largestFactor;
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}
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```
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</section>
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