sort array one by one

sort array one by one

<?php
// Sets up our arrays
$array1 = [1, 3, 5, 7, 9];
$array2 = [2, 4, 6, 8, 10];
$array3 = [];

// Determines how many items we have in each array
$array1_count = count($array1);
$array2_count = count($array2);

// While we still have at least one item in one of the arrays
while ($array1_count || $array2_count)
{
    $array1_empty = $array1 == [];
    $array2_empty = $array2 == [];

    if (!$array1_empty && !$array2_empty)
    {
        if (current($array1) < current($array2))
        {
            $array3[] = array_shift($array1);
            $array1_count--;
		
        }
        else
        {
            $array3[] = array_shift($array2);
            $array2_count--;
        }
    }
    elseif (!$array1_empty)
    {
        $array3[] = array_shift($array1);
        $array1_count--;
    }
    elseif (!$array2_empty)
    {
        $array3[] = array_shift($array2);
        $array2_count--;
    }
}