PHP Taskbook Level 4.3

Задание 1

Make a function that will take an array as a parameter and remove all duplicates from it.

Задание 2

Make a function that will take an array as a parameter and remove from it all duplicates that occur more than three times.

Задание 3

Make a function that will take an array as a parameter and remove identical, adjacent elements from it.

Задание 4

Create a function that takes an array of numbers as a parameter and returns the maximum and minimum values ​​from that array as the following array:

php[
  'max' => 9,
  'min' => 1,
]