14 lines
332 B
Markdown
14 lines
332 B
Markdown
### countOccurrences
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Counts the occurrences of a value in an array.
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Use `Array.reduce()` to increment a counter each time you encounter the specific value inside the array.
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```js
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const countOccurrences = (arr, value) => arr.reduce((a, v) => v === value ? a + 1 : a + 0, 0);
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```
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```js
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countOccurrences([1,1,2,1,2,3], 1) // 3
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```
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