求教消消乐算法。求指导！

Question

二，消消乐816。如下:1）字符818166816消除816后为空。2）字符81816816816消除后是81。

Answer 1

functionremoveStr($str){$pat='/816/';$res=preg_replace($pat,'',$str);returnpreg_match($pat,$res)?removeStr($res):$res;}

Answer 2

functionglops($str){$l=strlen($str);while($l>=3){$pos=strpos($str,'816');if($pos||$pos===0){$str=substr_replace($str,"",$pos,3);}else{break;}}return$str;}