세션확인 세션ID : 5q35of8t7c4a4c4lha9obg1o17
session1 :
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session2 :
Warning: Undefined array key "session2" in /users/2021/i2151020/public_html/2022/WebProg/ch10/exam10-05.php on line 12

session3 :
Warning: Undefined array key "session3" in /users/2021/i2151020/public_html/2022/WebProg/ch10/exam10-05.php on line 13

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