43 lines
1.1 KiB
Markdown
43 lines
1.1 KiB
Markdown
---
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id: 5900f4841000cf542c50ff97
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title: 'Problem 280: Ant and seeds'
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challengeType: 5
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forumTopicId: 301931
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dashedName: problem-280-ant-and-seeds
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---
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# --description--
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A laborious ant walks randomly on a 5x5 grid. The walk starts from the central square. At each step, the ant moves to an adjacent square at random, without leaving the grid; thus there are 2, 3 or 4 possible moves at each step depending on the ant's position.
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At the start of the walk, a seed is placed on each square of the lower row. When the ant isn't carrying a seed and reaches a square of the lower row containing a seed, it will start to carry the seed. The ant will drop the seed on the first empty square of the upper row it eventually reaches.
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What's the expected number of steps until all seeds have been dropped in the top row? Give your answer rounded to 6 decimal places.
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# --hints--
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`euler280()` should return 430.088247.
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```js
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assert.strictEqual(euler280(), 430.088247);
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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 euler280() {
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return true;
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}
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euler280();
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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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