47 lines
1.0 KiB
Markdown
47 lines
1.0 KiB
Markdown
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---
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id: 5900f3dd1000cf542c50fef0
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title: 'Problem 113: Non-bouncy numbers'
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challengeType: 5
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forumTopicId: 301739
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dashedName: problem-113-non-bouncy-numbers
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---
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# --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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# --hints--
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`euler113()` should return 51161058134250.
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```js
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assert.strictEqual(euler113(), 51161058134250);
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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 euler113() {
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return true;
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}
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euler113();
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```
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# --solutions--
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```js
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// solution required
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```
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