세션 ID : sc5a2l9gsfenjmkkd0q4vtn5u0
session1 :
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session2 :
Warning: Undefined array key "session2" in /users/2018/i1858020/public_html/2019/webprog/ch10/exam10-05.php on line 11

session3 :
Warning: Undefined array key "session3" in /users/2018/i1858020/public_html/2019/webprog/ch10/exam10-05.php on line 12

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