Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
14 lines
277 B
Markdown
14 lines
277 B
Markdown
### sum
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Returns the sum of two or more numbers/arrays.
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Use `Array.prototype.reduce()` to add each value to an accumulator, initialized with a value of `0`.
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```js
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const sum = (...arr) => [...arr].reduce((acc, val) => acc + val, 0);
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```
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```js
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sum(...[1, 2, 3, 4]); // 10
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```
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