49 lines
1.1 KiB
Markdown
49 lines
1.1 KiB
Markdown
---
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id: 5900f3ca1000cf542c50fedd
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title: 'Problem 94: Almost equilateral triangles'
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challengeType: 5
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forumTopicId: 302211
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dashedName: problem-94-almost-equilateral-triangles
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---
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# --description--
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It is easily proved that no equilateral triangle exists with integral length sides and integral area. However, the <dfn>almost equilateral triangle</dfn> 5-5-6 has an area of 12 square units.
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We shall define an <dfn>almost equilateral triangle</dfn> to be a triangle for which two sides are equal and the third differs by no more than one unit.
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Find the sum of the perimeters of all <dfn>almost equilateral triangle</dfn> with integral side lengths and area and whose perimeters do not exceed one billion (1,000,000,000).
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# --hints--
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`almostEquilateralTriangles()` should return a number.
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```js
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assert(typeof almostEquilateralTriangles() === 'number');
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```
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`almostEquilateralTriangles()` should return 518408346.
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```js
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assert.strictEqual(almostEquilateralTriangles(), 518408346);
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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 almostEquilateralTriangles() {
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return true;
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}
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almostEquilateralTriangles();
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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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