세션ID :
session1:
Warning: Undefined global variable $_SESSION in /users/2016/i1658006/public_html/2019/webprog/ch10/exam10-07.php on line 12

Warning: Trying to access array offset on null in /users/2016/i1658006/public_html/2019/webprog/ch10/exam10-07.php on line 12

session2:
Warning: Undefined global variable $_SESSION in /users/2016/i1658006/public_html/2019/webprog/ch10/exam10-07.php on line 13

Warning: Trying to access array offset on null in /users/2016/i1658006/public_html/2019/webprog/ch10/exam10-07.php on line 13

session3:
Warning: Undefined global variable $_SESSION in /users/2016/i1658006/public_html/2019/webprog/ch10/exam10-07.php on line 14

Warning: Trying to access array offset on null in /users/2016/i1658006/public_html/2019/webprog/ch10/exam10-07.php on line 14

세션설정
세션확인
세션변수 session1 삭제
세션삭제