63 lines
1.2 KiB
Markdown
63 lines
1.2 KiB
Markdown
---
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id: 5900f4b01000cf542c50ffc2
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challengeType: 5
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title: 'Problem 323: Bitwise-OR operations on random integers'
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---
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## Description
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<section id='description'>
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Let y0, y1, y2,... be a sequence of random unsigned 32 bit integers
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(i.e. 0 ≤ yi < 232, every value equally likely).
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For the sequence xi the following recursion is given:x0 = 0 and
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xi = xi-1| yi-1, for i > 0. ( | is the bitwise-OR operator)
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It can be seen that eventually there will be an index N such that xi = 232 -1 (a bit-pattern of all ones) for all i ≥ N.
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Find the expected value of N.
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Give your answer rounded to 10 digits after the decimal point.
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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>euler323()</code> should return 6.3551758451.
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testString: 'assert.strictEqual(euler323(), 6.3551758451, "<code>euler323()</code> should return 6.3551758451.");'
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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 euler323() {
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// Good luck!
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return true;
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}
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euler323();
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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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