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
1.0 KiB
Markdown
49 lines
1.0 KiB
Markdown
---
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id: 5900f4a31000cf542c50ffb6
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title: 'Problem 311: Biclinic Integral Quadrilaterals'
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challengeType: 5
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forumTopicId: 301967
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dashedName: problem-311-biclinic-integral-quadrilaterals
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---
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# --description--
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ABCD is a convex, integer sided quadrilateral with 1 ≤ AB < BC < CD < AD.
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BD has integer length. O is the midpoint of BD. AO has integer length.
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We'll call ABCD a biclinic integral quadrilateral if AO = CO ≤ BO = DO.
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For example, the following quadrilateral is a biclinic integral quadrilateral: AB = 19, BC = 29, CD = 37, AD = 43, BD = 48 and AO = CO = 23.
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Let B(N) be the number of distinct biclinic integral quadrilaterals ABCD that satisfy AB2+BC2+CD2+AD2 ≤ N. We can verify that B(10 000) = 49 and B(1 000 000) = 38239.
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Find B(10 000 000 000).
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# --hints--
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`euler311()` should return 2466018557.
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```js
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assert.strictEqual(euler311(), 2466018557);
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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 euler311() {
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return true;
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}
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euler311();
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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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