ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
49 lines
949 B
Markdown
49 lines
949 B
Markdown
---
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id: 5900f4b01000cf542c50ffc2
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title: 'Problem 323: Bitwise-OR operations on random integers'
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challengeType: 5
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forumTopicId: 301980
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dashedName: problem-323-bitwise-or-operations-on-random-integers
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---
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# --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. Give your answer rounded to 10 digits after the decimal point.
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# --hints--
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`euler323()` should return 6.3551758451.
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```js
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assert.strictEqual(euler323(), 6.3551758451);
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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 euler323() {
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return true;
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}
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euler323();
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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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