Who Left the Array?

You are given two arrays. The elements in arr1 threw a party and started to mix around. However, one of the elements got lost! Your task is to return the element which was lost.

Examples

missing([1, 2, 3, 4, 5, 6, 7, 8], [1, 3, 4, 5, 6, 7, 8]) ➞ 2

missing([true, true, false, false, true], [false, true, false, true]) ➞ true

missing(["Jane", "is", "pretty", "ugly"], ["Jane", "is", "pretty"]) ➞ "ugly"

Notes

• Assume that the first array always contains 1 or more elements.
• Elements are always lost.
• An element can also have duplicates.