<?php

$rce = $_GET['rce'];
if (isset($rce)) {
    if (!preg_match("/cat|more|less|head|tac|tail|nl|od|vi|vim|sort|flag| |\;|[0-9]|*|\`|\%|\>|\<|\'|\"/i", $rce)) {
        system($rce);
    }else {
        echo "hhhhhhacker!!!"."\n";
    }
} else {
    highlight_file(__FILE__);
}