Online PHP editor | output for snc6s

<?php abstract class Lol { abstract public static function run(); public static function onceLol() { if (static::$cache!==NULL) { return static::$cache; } static::$cache = static::run(); return static::$cache; } } class Lol1 extends Lol { protected static $cache = NULL; public static function run() { echo "Lol1\n"; return 'PHP is the best language in the shit'; } } class Lol2 extends Lol { protected static $cache = NULL; public static function run() { echo "Lol2\n"; return 'Just lol'; } } echo Lol1::onceLol(); // echoing 'PHP is the best language in the shit' from Lol1 echo "\n"; echo Lol2::onceLol(); // echoing 'PHP is the best language in the shit' from Lol1 echo "\n"; echo Lol1::onceLol(); // echoing 'PHP is the best language in the shit' from Lol1 echo "\n"; echo Lol2::onceLol(); // echoing 'PHP is the best language in the shit' from Lol1