Get elements that occur in both arrays

You want a function that takes two arrays and returns an array containing only the elements that occur in both:

const arr1 = [2, 4, 6, 8]
const arr2 = [2, 10, 6, 15]

console.log(sharedElements) // [2, 6]

Here’s how:

const sharedElements = arr1.filter(arr1Element => {
  return arr2.includes(arr1Element)
})