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30-seconds-of-code/snippets/countOccurrences.md
2017-12-18 00:51:27 +01:00

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