세션변수 session1 삭제 세션ID : gv3mh1dvtfnb709qqf4fc3ji8n
session1 :
Warning: Undefined array key "session1" in /users/2019/i1919029/public_html/2022/WebProg/ch10/exam10-06.php on line 13

session2 :
Warning: Undefined array key "session2" in /users/2019/i1919029/public_html/2022/WebProg/ch10/exam10-06.php on line 14

session3 :
Warning: Undefined array key "session3" in /users/2019/i1919029/public_html/2022/WebProg/ch10/exam10-06.php on line 15

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