How to properly group a php array?

Question

PHP

Good afternoon. I sit, racking my brains on how to group such an array:

array(
  "/home/fol1/test.txt",
  "/home/fol1/Browsers/test2.txt",
  "/home/fol2/Browsers/test3.txt",
  "/home/fol2/Browsers/ttre/test2.txt"
)

In this one:

аrrау(

  "fol1" => array (
  "/home/fol1/test.txt",
  "/home/fol1/Browsers/test2.txt"
  ),

  "fol2" => array (
   "/home/fol2/Browsers/test3.txt",
  "/home/fol2/Browsers/ttre/test2.txt"
  )
);

Answer 1

foreach ($arr as $el) {
  $grouped[explode('/', $el)[2]][] = $el;
}