45 lines
884 B
Markdown
45 lines
884 B
Markdown
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---
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id: 5900f4431000cf542c50ff56
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title: 'Problem 215: Crack-free Walls'
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challengeType: 5
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forumTopicId: 301857
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dashedName: problem-215-crack-free-walls
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---
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# --description--
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Consider the problem of building a wall out of 2×1 and 3×1 bricks (horizontal×vertical dimensions) such that, for extra strength, the gaps between horizontally-adjacent bricks never line up in consecutive layers, i.e. never form a "running crack".
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For example, the following 9×3 wall is not acceptable due to the running crack shown in red:
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There are eight ways of forming a crack-free 9×3 wall, written W(9,3) = 8.
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Calculate W(32,10).
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# --hints--
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`euler215()` should return 806844323190414.
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```js
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assert.strictEqual(euler215(), 806844323190414);
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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 euler215() {
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return true;
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}
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euler215();
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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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