세션ID: mhgngqqqj41975kthe0uhj2lvi
session1:
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session2:
Warning: Undefined array key "session2" in /users/2021/i2151059/public_html/2022/WebProg/ch10/exam10-07.php on line 15

session3:
Warning: Undefined array key "session3" in /users/2021/i2151059/public_html/2022/WebProg/ch10/exam10-07.php on line 16

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