3v4l.org

run code in 500+ PHP versions simultaneously
<?php $arr = [ ['96','90','91'], ['96','90','91'], ['96','90','91','98'], ['96','90','91','98'], ]; $set = []; foreach ($arr as $values) { foreach($values as $each_value){ if(!isset($set[$each_value])) $set[$each_value] = true; } } $result = []; $set = array_keys($set); foreach ($arr as $values) { foreach($set as $value){ if(!in_array($value,$values)) $result[] = $value; } } $result = array_unique($result); print_r($result);
Output for 7.1.25 - 7.1.30, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Array ( [0] => 98 )

preferences:
112.32 ms | 1426 KiB | 4 Q