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74 lines
1.2 KiB
Markdown
74 lines
1.2 KiB
Markdown
---
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id: a302f7aae1aa3152a5b413bc
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title: Factorialize a Number
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challengeType: 1
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forumTopicId: 16013
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dashedName: factorialize-a-number
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---
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# --description--
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Return the factorial of the provided integer.
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If the integer is represented with the letter `n`, a factorial is the product of all positive integers less than or equal to `n`.
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Factorials are often represented with the shorthand notation `n!`
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For example: `5! = 1 * 2 * 3 * 4 * 5 = 120`
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Only integers greater than or equal to zero will be supplied to the function.
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# --hints--
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`factorialize(5)` should return a number.
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```js
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assert.isNumber(factorialize(5));
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```
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`factorialize(5)` should return `120`.
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```js
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assert.strictEqual(factorialize(5), 120);
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```
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`factorialize(10)` should return `3628800`.
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```js
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assert.strictEqual(factorialize(10), 3628800);
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```
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`factorialize(20)` should return `2432902008176640000`.
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```js
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assert.strictEqual(factorialize(20), 2432902008176640000);
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```
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`factorialize(0)` should return `1`.
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```js
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assert.strictEqual(factorialize(0), 1);
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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 factorialize(num) {
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return num;
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}
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factorialize(5);
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```
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# --solutions--
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```js
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function factorialize(num) {
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return num < 1 ? 1 : num * factorialize(num - 1);
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}
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factorialize(5);
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```
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