47 lines
1.0 KiB
Markdown
47 lines
1.0 KiB
Markdown
---
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id: 5900f4ca1000cf542c50ffdc
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title: 'Problem 349: Langton''s ant'
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challengeType: 5
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forumTopicId: 302008
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dashedName: problem-349-langtons-ant
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---
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# --description--
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An ant moves on a regular grid of squares that are coloured either black or white.
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The ant is always oriented in one of the cardinal directions (left, right, up or down) and moves from square to adjacent square according to the following rules:
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\- if it is on a black square, it flips the color of the square to white, rotates 90 degrees counterclockwise and moves forward one square.
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\- if it is on a white square, it flips the color of the square to black, rotates 90 degrees clockwise and moves forward one square.
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Starting with a grid that is entirely white, how many squares are black after 1018 moves of the ant?
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# --hints--
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`euler349()` should return 115384615384614940.
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```js
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assert.strictEqual(euler349(), 115384615384614940);
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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 euler349() {
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return true;
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}
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euler349();
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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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