29 lines
844 B
Markdown
29 lines
844 B
Markdown
---
|
|
title: isContainedIn
|
|
tags: array,intermediate
|
|
---
|
|
|
|
Returns `true` if the elements of the first array are contained in the second one regardless of order, `false` otherwise.
|
|
|
|
Use a `for...of` loop over a `Set` created from the first array.
|
|
Use `Array.prototype.some()` to check if all distinct values are contained in the second array, use `Array.prototype.filter()` to compare the amount of occurences of each distinct value in both arrays.
|
|
Return `false` if the count of any element is greater in the first array than the second one, `true` otherwise.
|
|
|
|
```js
|
|
|
|
const isContainedIn = (a, b) => {
|
|
for (const v of new Set(a)) {
|
|
if (
|
|
!b.some(e => e === v) ||
|
|
a.filter(e => e === v).length > b.filter(e => e === v).length
|
|
)
|
|
return false;
|
|
}
|
|
return true;
|
|
};
|
|
```
|
|
|
|
```js
|
|
isContainedIn([1, 4], [2, 4, 1]); // true
|
|
```
|