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>
54 lines
886 B
Markdown
54 lines
886 B
Markdown
---
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id: 5900f4151000cf542c50ff28
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title: >-
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Problem 169: Exploring the number of different ways a number can be expressed
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as a sum of powers of 2
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challengeType: 5
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forumTopicId: 301803
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dashedName: >-
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problem-169-exploring-the-number-of-different-ways-a-number-can-be-expressed-as-a-sum-of-powers-of-2
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---
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# --description--
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Define f(0)=1 and f(n) to be the number of different ways n can be expressed as a sum of integer powers of 2 using each power no more than twice.
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For example, f(10)=5 since there are five different ways to express 10:
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1 + 1 + 8
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1 + 1 + 4 + 41 + 1 + 2 + 2 + 4
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2 + 4 + 4
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2 + 8
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What is f(1025)?
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# --hints--
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`euler169()` should return 178653872807.
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```js
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assert.strictEqual(euler169(), 178653872807);
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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 euler169() {
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return true;
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}
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euler169();
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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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