세션ID: qsast8gihqdbtvitp4tsufn3mq
session1:
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session2:
Warning: Undefined array key "session2" in /users/2021/i2151048/public_html/2022/WebProg/ch10/exam10-05.php on line 12

session3:
Warning: Undefined array key "session3" in /users/2021/i2151048/public_html/2022/WebProg/ch10/exam10-05.php on line 13

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