3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = [ ['A', 1], 'B', ['C', 2], 'D', 'E', ['F', 3], ]; print json_encode(array_column($arr, null, 1), JSON_PRETTY_PRINT);

preferences:
28.51 ms | 402 KiB | 5 Q