62 lines
935 B
Markdown
62 lines
935 B
Markdown
---
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id: 5900f4e11000cf542c50fff3
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challengeType: 5
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title: 'Problem 372: Pencils of rays'
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---
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## Description
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<section id='description'>
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Let R(M, N) be the number of lattice points (x, y) which satisfy M<x≤N, M<y≤N and is odd.
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We can verify that R(0, 100) = 3019 and R(100, 10000) = 29750422.
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Find R(2·106, 109).
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Note: represents the floor function.
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</section>
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## Instructions
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<section id='instructions'>
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>euler372()</code> should return 301450082318807040.
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testString: assert.strictEqual(euler372(), 301450082318807040, '<code>euler372()</code> should return 301450082318807040.');
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function euler372() {
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// Good luck!
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return true;
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}
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euler372();
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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