49 lines
768 B
Markdown
49 lines
768 B
Markdown
---
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id: 5900f4c21000cf542c50ffd4
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title: 'Problem 340: Crazy Function'
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challengeType: 5
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forumTopicId: 301999
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dashedName: problem-340-crazy-function
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---
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# --description--
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For fixed integers a, b, c, define the crazy function F(n) as follows:
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F(n) = n - c for all n > b
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F(n) = F(a + F(a + F(a + F(a + n)))) for all n ≤ b.
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Also, define S(a, b, c) = .
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For example, if a = 50, b = 2000 and c = 40, then F(0) = 3240 and F(2000) = 2040. Also, S(50, 2000, 40) = 5204240.
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Find the last 9 digits of S(217, 721, 127).
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# --hints--
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`euler340()` should return 291504964.
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```js
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assert.strictEqual(euler340(), 291504964);
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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 euler340() {
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return true;
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}
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euler340();
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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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