How to fixed? still Show Notice on this [duplicate]

This question already has an answer here:

• PHP: “Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” 24 answers

How to fixed this still show :

Notice: Undefined index: endquiz in /opt/lampp/htdocs/new2c/account.php on line 379

Notice: Undefined index: total in /opt/lampp/htdocs/new2c/account.php on line 489

Notice: Undefined index: total in /opt/lampp/htdocs/new2c/account.php on line 510

My codes:

account.php :https://ideone.com/3u3KSu 

qupdate.php https://ideone.com/TUi0V6