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>
67 lines
1.2 KiB
Markdown
67 lines
1.2 KiB
Markdown
---
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id: 5900f3911000cf542c50fea4
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title: 'Problem 37: Truncatable primes'
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challengeType: 5
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forumTopicId: 302031
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dashedName: problem-37-truncatable-primes
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---
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# --description--
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The number 3797 has an interesting property. Being prime itself, it is possible to continuously remove digits from left to right, and remain prime at each stage: 3797, 797, 97, and 7. Similarly we can work from right to left: 3797, 379, 37, and 3.
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Find the sum of the only `n` (8 ≤ `n` ≤ 11) primes that are both truncatable from left to right and right to left.
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NOTE: 2, 3, 5, and 7 are not considered to be truncatable primes.
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# --hints--
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`truncatablePrimes(8)` should return a number.
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```js
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assert(typeof truncatablePrimes(8) === 'number');
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```
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`truncatablePrimes(8)` should return 1986.
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```js
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assert(truncatablePrimes(8) == 1986);
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```
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`truncatablePrimes(9)` should return 5123.
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```js
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assert(truncatablePrimes(9) == 5123);
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```
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`truncatablePrimes(10)` should return 8920.
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```js
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assert(truncatablePrimes(10) == 8920);
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```
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`truncatablePrimes(11)` should return 748317.
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```js
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assert(truncatablePrimes(11) == 748317);
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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 truncatablePrimes(n) {
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return n;
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}
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truncatablePrimes(11);
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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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