<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div>Hi Ben,</div><div><br></div><div>Thank you for your comments! Here is a new version. In this version, I still kept some “if” thinking that some operand has been already extracted so I would like to use it directly. Please let me know if any other comments. </div></body></html>