I have this array (it's just a part of it). 6 = question ID, optionIDs = possible answers.
Array
(
[3] => Array
(
[0] => 6
[1] => Array
(
[0] => Array
(
[optionID] => 16
[isCorrect] => 0
)
[1] => Array
(
[optionID] => 14
[isCorrect] => 1
)
[2] => Array
(
[optionID] => 15
[isCorrect] => 0
)
[3] => Array
(
[optionID] => 17
[isCorrect] => 0
)
)
)
[7] => Array
(
[0] => 6
[1] => Array
(
[0] => Array
(
[optionID] => 16
[isCorrect] => 0
)
[1] => Array
(
[optionID] => 15
[isCorrect] => 0
)
[2] => Array
(
[optionID] => 17
[isCorrect] => 0
)
[3] => Array
(
[optionID] => 14
[isCorrect] => 1
)
)
)
)
I'm trying to merge redundant questions (6 and 6) with array_map:
$unique = array_map('unserialize', array_unique(array_map('serialize', $quizQuestionArray)));
And it works as long as optionIDs are in the same order. But in some cases (like here) they are shuffled (16,14,15,17) (16,15,17,14). Is there a way to keep them shuffled and remove duplicate questions?
array_map-serialize is a pretty crude way to deduplicate an array. You should be using something like this instead:
$dupeIds = [];
$array = array_filter($array, function ($item) use (&$dupeIds) {
$keep = !isset($dupeIds[$item[0]]);
$dupeIds[$item[0]] = true;
return $keep;
});