3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr1 = array("1","3","4","6"); $arr2 = array("2","3","4","5","7"); foreach($arr1 as $k => $v){ foreach($arr2 as $k1 => $v1){ if($v == $v1){ unset($arr1[$k]);break; } } } print_r($arr1);
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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
Array ( [0] => 1 [3] => 6 )

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