3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array(array( "2"=> 6, "5"=> 1 ), array( "2"=> 1, "5"=> 3 )); $arr = []; $keys = array_keys(reset($arr) ?: []); $res = array_combine( $keys, array_map( fn ($k) => max(array_column($arr, $k)), $keys) ); print_r($res);

preferences:
36.52 ms | 410 KiB | 5 Q