세션변수 session1 삭제 세션ID : 66qb00tdqlbjh3aet2vfn6meu8
session1 :
Warning: Undefined array key "session1" in /users/2018/i1858067/public_html/2019/webprog/ch10/exam10-06.php on line 13

session2 :
Warning: Undefined array key "session2" in /users/2018/i1858067/public_html/2019/webprog/ch10/exam10-06.php on line 14

session3 :
Warning: Undefined array key "session3" in /users/2018/i1858067/public_html/2019/webprog/ch10/exam10-06.php on line 15

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