세션 ID : 94l4ec2u37sik4gosti3soc8k1
session1 :
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session2 :
Warning: Undefined array key "session2" in /users/2018/i1858006/public_html/2019/webprog/ch10/exam10-08.php on line 17

session3 :
Warning: Undefined array key "session3" in /users/2018/i1858006/public_html/2019/webprog/ch10/exam10-08.php on line 18

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