76 lines
1.8 KiB
Markdown
76 lines
1.8 KiB
Markdown
---
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id: 5900f3971000cf542c50feaa
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title: 'Problem 43: Sub-string divisibility'
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challengeType: 5
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forumTopicId: 302100
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dashedName: problem-43-sub-string-divisibility
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---
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# --description--
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The number, 1406357289, is a 0 to 9 pandigital number because it is made up of each of the digits 0 to 9 in some order, but it also has a rather interesting sub-string divisibility property.
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Let d<sub>1</sub> be the 1<sup>st</sup> digit, d<sub>2</sub> be the 2<sup>nd</sup> digit, and so on. In this way, we note the following:
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<ul>
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<li>d<sub>2</sub>d<sub>3</sub>d<sub>4</sub> = 406 is divisible by 2</li>
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<li>d<sub>3</sub>d<sub>4</sub>d<sub>5</sub> = 063 is divisible by 3</li>
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<li>d<sub>4</sub>d<sub>5</sub>d<sub>6</sub> = 635 is divisible by 5</li>
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<li>d<sub>5</sub>d<sub>6</sub>d<sub>7</sub> = 357 is divisible by 7</li>
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<li>d<sub>6</sub>d<sub>7</sub>d<sub>8</sub> = 572 is divisible by 11</li>
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<li>d<sub>7</sub>d<sub>8</sub>d<sub>9</sub> = 728 is divisible by 13</li>
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<li>d<sub>8</sub>d<sub>9</sub>d<sub>10</sub> = 289 is divisible by 17</li>
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</ul>
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Find the numbers of all 0 to 9 pandigital numbers with this property.
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# --hints--
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`substringDivisibility()` should return an array.
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```js
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assert(Array.isArray(substringDivisibility()));
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```
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`substringDivisibility()` should return [ 1430952867, 1460357289, 1406357289, 4130952867, 4160357289, 4106357289 ].
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```js
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assert.sameMembers(substringDivisibility(), [
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1430952867,
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1460357289,
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1406357289,
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4130952867,
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4160357289,
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4106357289
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]);
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```
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You should not copy and return the array.
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```js
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assert(
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!code.match(
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/(1430952867)|(1460357289)|(1406357289)|(4130952867)|(4160357289)|(4106357289)/
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)
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);
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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 substringDivisibility() {
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return [];
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}
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substringDivisibility();
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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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