3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr1 = array( 'a' => 'Apple', 'b' => 'Banana' ); $arr2 = array( 'b' => 'Banana', 'a' => 'Australia', 'Apple' ); $arr3 = array_diff($arr1, $arr2); $arr4 = array_diff($arr2, $arr1); $keys = array_keys($arr4); echo count($arr3) . ' - ' . $keys[0]; ?>
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.30, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.17 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
0 - a
preferences:
235.37 ms | 406 KiB | 397 Q