67 lines
1.5 KiB
Markdown
67 lines
1.5 KiB
Markdown
---
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id: 5900f3841000cf542c50fe97
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title: 'Problem 24: Lexicographic permutations'
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challengeType: 5
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forumTopicId: 301885
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dashedName: problem-24-lexicographic-permutations
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---
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# --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 `n`th lexicographic permutation of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9?
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# --hints--
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`lexicographicPermutations(699999)` should return a number.
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```js
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assert(typeof lexicographicPermutations(699999) === 'number');
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```
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`lexicographicPermutations(699999)` should return 1938246570.
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```js
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assert(lexicographicPermutations(699999) == 1938246570);
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```
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`lexicographicPermutations(899999)` should return 2536987410.
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```js
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assert(lexicographicPermutations(899999) == 2536987410);
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```
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`lexicographicPermutations(900000)` should return 2537014689.
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```js
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assert(lexicographicPermutations(900000) == 2537014689);
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```
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`lexicographicPermutations(999999)` should return 2783915460.
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```js
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assert(lexicographicPermutations(999999) == 2783915460);
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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 lexicographicPermutations(n) {
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return n;
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}
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lexicographicPermutations(999999);
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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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