75 lines
1.2 KiB
Markdown
75 lines
1.2 KiB
Markdown
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---
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id: 597f1e7fbc206f0e9ba95dc4
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title: Factors of an integer
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challengeType: 5
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forumTopicId: 302265
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dashedName: factors-of-an-integer
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---
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# --description--
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Write a function that returns the factors of a positive integer as an array.
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These factors are the positive integers by which the number being factored can be divided to yield a positive integer result.
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# --hints--
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`factors` should be a function.
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```js
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assert(typeof factors === 'function');
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```
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`factors(45)` should return `[1,3,5,9,15,45]`.
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```js
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assert.deepEqual(factors(45), ans[0]);
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```
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`factors(53)` should return `[1,53]`.
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```js
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assert.deepEqual(factors(53), ans[1]);
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```
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`factors(64)` should return `[1,2,4,8,16,32,64]`.
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```js
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assert.deepEqual(factors(64), ans[2]);
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```
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# --seed--
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## --after-user-code--
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```js
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const ans=[[1,3,5,9,15,45],[1,53],[1,2,4,8,16,32,64]];
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```
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## --seed-contents--
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```js
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function factors(num) {
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}
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```
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# --solutions--
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```js
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function factors(num)
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{
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let n_factors = [], i, sqr=Math.floor(Math.sqrt(num));
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for (i = 1; i <=sqr ; i += 1)
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if (num % i === 0)
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{
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n_factors.push(i);
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if (num / i !== i)
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n_factors.push(num / i);
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}
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n_factors.sort(function(a, b){return a - b;});
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return n_factors;
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}
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```
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