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---
id: 5900f43f1000cf542c50ff51
title: 'Problem 208: Robot Walks'
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challengeType: 5
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forumTopicId: 301849
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dashedName: problem-208-robot-walks
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---
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# --description--
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A robot moves in a series of one-fifth circular arcs (72°), with a free choice of a clockwise or an anticlockwise arc for each step, but no turning on the spot.
One of 70932 possible closed paths of 25 arcs starting northward is
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< img class = "img-responsive center-block" alt = "closed path of 25 arcs, starting northward" src = "https://cdn.freecodecamp.org/curriculum/project-euler/robot-walks.gif" style = "background-color: white; padding: 10px;" >
Given that the robot starts facing North, how many journeys of 70 arcs in length can it take that return it, after the final arc, to its starting position?
**Note:** Any arc may be traversed multiple times.
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# --hints--
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`robotWalks()` should return `331951449665644800` .
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```js
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assert.strictEqual(robotWalks(), 331951449665644800);
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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 robotWalks() {
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return true;
}
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robotWalks();
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```
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# --solutions--
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```js
// solution required
```