How can developers optimize their code when using array_unique in PHP to improve performance?

When using array_unique in PHP, developers can optimize their code by using a combination of array_values and array_flip to remove duplicates efficiently. This method ensures that the array keys are re-indexed numerically after removing duplicates, which can improve performance when working with large arrays.

// Original array with duplicates
$array = [1, 2, 2, 3, 4, 4, 5];

// Remove duplicates efficiently
$uniqueArray = array_values(array_flip(array_flip($array)));

print_r($uniqueArray);