45 lines
1.1 KiB
Markdown
45 lines
1.1 KiB
Markdown
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---
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id: 5900f3ff1000cf542c50ff12
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title: 'Problem 147: Rectangles in cross-hatched grids'
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challengeType: 5
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forumTopicId: 301776
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dashedName: problem-147-rectangles-in-cross-hatched-grids
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---
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# --description--
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In a 3x2 cross-hatched grid, a total of 37 different rectangles could be situated within that grid as indicated in the sketch.
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There are 5 grids smaller than 3x2, vertical and horizontal dimensions being important, i.e. 1x1, 2x1, 3x1, 1x2 and 2x2. If each of them is cross-hatched, the following number of different rectangles could be situated within those smaller grids: 1x1: 1 2x1: 4 3x1: 8 1x2: 4 2x2: 18
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Adding those to the 37 of the 3x2 grid, a total of 72 different rectangles could be situated within 3x2 and smaller grids.
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How many different rectangles could be situated within 47x43 and smaller grids?
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# --hints--
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`euler147()` should return 846910284.
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```js
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assert.strictEqual(euler147(), 846910284);
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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 euler147() {
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return true;
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}
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euler147();
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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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