세션ID : kts8o8fojdjhbjsnkms7d7h2es
session1 :
Warning: Undefined array key "session1" in /users/2016/i1658010/public_html/2019/webprog/ch10/exam10-07.php on line 13

session2 :
Warning: Undefined array key "session2" in /users/2016/i1658010/public_html/2019/webprog/ch10/exam10-07.php on line 14

session3 :
Warning: Undefined array key "session3" in /users/2016/i1658010/public_html/2019/webprog/ch10/exam10-07.php on line 15

세션설정
세션확인
모든세션변수삭제
세션삭제