How to split an array into pairs of different elements in PHP randomly?

Question

Example:

$atletas = array("A", "B", "C", "D", "E", "Bye", "Bye", "Bye");

My function:

function sortear_grelha($atletas) {
        shuffle($atletas);
        $atletas = array_chunk($atletas, 2);
        return $atletas;
}

Expected result for example:

[["A","Bye"],["C","Bye"],["Bye","D"],["B","E"]]

The output I am getting:

[["A","Bye"],["Bye","Bye"],["C","D"],["B","E"]]

I want pairs of different values.

Answer 1

Here's one that works by calling sortear_grelha() recursively until there are no duplicates in a pair:

function sortear_grelha($atletas) {
        shuffle($atletas);
        $result = array_chunk($atletas, 2);

        if(array_map('array_unique', $result) != $result) {
            return sortear_grelha($atletas);
        }
        return $result;
}