3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = [ 'a' => 0, 'b' => 0, 'c' => 1 ]; var_export( array_reduce( array_keys($a), function ($result, $k) use ($a) { $result[$a[$k]][] = $k; return $result; } ) );

This is an error 500

Value for `_results` contains invalid data `array`


preferences:
159.99 ms | 1606 KiB | 13 Q