60 lines
1.3 KiB
Markdown
60 lines
1.3 KiB
Markdown
---
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id: 5900f3dd1000cf542c50fef0
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challengeType: 5
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title: 'Problem 113: Non-bouncy numbers'
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---
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## Description
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<section id='description'>
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Working from left-to-right if no digit is exceeded by the digit to its left it is called an increasing number; for example, 134468.
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Similarly if no digit is exceeded by the digit to its right it is called a decreasing number; for example, 66420.
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We shall call a positive integer that is neither increasing nor decreasing a "bouncy" number; for example, 155349.
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As n increases, the proportion of bouncy numbers below n increases such that there are only 12951 numbers below one-million that are not bouncy and only 277032 non-bouncy numbers below 1010.
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How many numbers below a googol (10100) are not bouncy?
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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>euler113()</code> should return 51161058134250.
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testString: 'assert.strictEqual(euler113(), 51161058134250, "<code>euler113()</code> should return 51161058134250.");'
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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 euler113() {
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// Good luck!
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return true;
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}
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euler113();
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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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