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>
82 lines
1.3 KiB
Markdown
82 lines
1.3 KiB
Markdown
---
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id: 5900f3761000cf542c50fe89
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title: 'Problem 10: Summation of primes'
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challengeType: 5
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forumTopicId: 301723
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dashedName: problem-10-summation-of-primes
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---
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# --description--
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The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
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Find the sum of all the primes below `n`.
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# --hints--
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`primeSummation(17)` should return a number.
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```js
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assert(typeof primeSummation(17) === 'number');
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```
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`primeSummation(17)` should return 41.
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```js
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assert.strictEqual(primeSummation(17), 41);
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```
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`primeSummation(2001)` should return 277050.
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```js
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assert.strictEqual(primeSummation(2001), 277050);
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```
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`primeSummation(140759)` should return 873608362.
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```js
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assert.strictEqual(primeSummation(140759), 873608362);
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```
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`primeSummation(2000000)` should return 142913828922.
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```js
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assert.strictEqual(primeSummation(2000000), 142913828922);
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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 primeSummation(n) {
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return true;
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}
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primeSummation(2000000);
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```
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# --solutions--
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```js
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function primeSummation(n) {
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if (n < 3) { return 0 };
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let nums = [0, 0, 2];
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for (let i = 3; i < n; i += 2){
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nums.push(i);
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nums.push(0);
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}
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let sum = 2;
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for (let i = 3; i < n; i += 2){
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if (nums[i] !== 0){
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sum += nums[i];
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for (let j = i*i; j < n; j += i){
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nums[j] = 0;
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}
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}
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}
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return sum;
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}
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```
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