세션 ID : rn5a3o6r2np4e9kr3fs1ch6qth
session1 :
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session2 :
Warning: Undefined array key "session2" in /users/2020/i2040029/public_html/2022/WebProg/ch10/exam10-05.php on line 11

session3 :
Warning: Undefined array key "session3" in /users/2020/i2040029/public_html/2022/WebProg/ch10/exam10-05.php on line 12

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