63 lines
1.9 KiB
Markdown
63 lines
1.9 KiB
Markdown
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---
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id: 5900f3841000cf542c50fe97
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challengeType: 5
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title: 'Problem 24: Lexicographic permutations'
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---
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## Description
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<section id='description'>
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A permutation is an ordered arrangement of objects. For example, 3124 is one possible permutation of the digits 1, 2, 3 and 4. If all of the permutations are listed numerically or alphabetically, we call it lexicographic order. The lexicographic permutations of 0, 1 and 2 are:
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<div style='text-align: center;'>012 021 102 120 201 210</div>
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What is the <var>n</var>th lexicographic permutation of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9?
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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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- text: <code>lexicographicPermutations(699999)</code> should return 1938246570.
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testString: 'assert(lexicographicPermutations(699999) == 1938246570, "<code>lexicographicPermutations(699999)</code> should return 1938246570.");'
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- text: <code>lexicographicPermutations(899999)</code> should return 2536987410.
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testString: 'assert(lexicographicPermutations(899999) == 2536987410, "<code>lexicographicPermutations(899999)</code> should return 2536987410.");'
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- text: <code>lexicographicPermutations(900000)</code> should return 2537014689.
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testString: 'assert(lexicographicPermutations(900000) == 2537014689, "<code>lexicographicPermutations(900000)</code> should return 2537014689.");'
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- text: <code>lexicographicPermutations(999999)</code> should return 2783915460.
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testString: 'assert(lexicographicPermutations(999999) == 2783915460, "<code>lexicographicPermutations(999999)</code> should return 2783915460.");'
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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 lexicographicPermutations(n) {
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// Good luck!
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return n;
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}
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lexicographicPermutations(999999);
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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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