2021-06-15 07:49:18 +00:00
|
|
|
---
|
|
|
|
id: 597b2b2a2702b44414742771
|
2021-08-09 08:35:35 +00:00
|
|
|
title: Fatorial
|
2021-06-15 07:49:18 +00:00
|
|
|
challengeType: 5
|
|
|
|
forumTopicId: 302263
|
|
|
|
dashedName: factorial
|
|
|
|
---
|
|
|
|
|
|
|
|
# --description--
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
Escreva uma função que retorne o fatorial de um número.
|
2021-06-15 07:49:18 +00:00
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
O fatorial de um número é dado por:
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
<pre><big>n! = n * (n-1) * (n-2) * ..... * 1</big>
|
|
|
|
</pre>
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
Por exemplo:
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
<ul>
|
|
|
|
<li><code>3! = 3 * 2 * 1 = 6</code></li>
|
|
|
|
<li><code>4! = 4 * 3 * 2 * 1 = 24</code></li>
|
|
|
|
</ul>
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
**Observação:** `0! = 1`
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
# --hints--
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
`factorial` deve ser uma função.
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
```js
|
|
|
|
assert(typeof factorial === 'function');
|
|
|
|
```
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
`factorial(2)` deve retornar um número.
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
```js
|
|
|
|
assert(typeof factorial(2) === 'number');
|
|
|
|
```
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
`factorial(3)` deve retornar 6.
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
```js
|
|
|
|
assert.equal(factorial(3), 6);
|
|
|
|
```
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
`factorial(5)` deve retornar 120.
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
```js
|
|
|
|
assert.equal(factorial(5), 120);
|
|
|
|
```
|
|
|
|
|
2021-08-09 08:35:35 +00:00
|
|
|
`factorial(10)` deve retornar 3,628,800.
|
2021-06-15 07:49:18 +00:00
|
|
|
|
|
|
|
```js
|
|
|
|
assert.equal(factorial(10), 3628800);
|
|
|
|
```
|
|
|
|
|
|
|
|
# --seed--
|
|
|
|
|
|
|
|
## --seed-contents--
|
|
|
|
|
|
|
|
```js
|
|
|
|
function factorial(n) {
|
|
|
|
|
|
|
|
}
|
|
|
|
```
|
|
|
|
|
|
|
|
# --solutions--
|
|
|
|
|
|
|
|
```js
|
|
|
|
function factorial(n) {
|
|
|
|
let sum = 1;
|
|
|
|
while (n > 1) {
|
|
|
|
sum *= n;
|
|
|
|
n--;
|
|
|
|
}
|
|
|
|
return sum;
|
|
|
|
}
|
|
|
|
```
|