In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
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Question: aIZIsqL, wxSZIsEnO

Answer: ZIs


Question: ocjsZZfSBBopDtgWUT, rWmgzsZZfSBBoGWQ

Answer: sZZfSBBo


Question: DAUQmQgkmKHfqjWXO, ISQmQgkmKxzp

Answer:
QmQgkmK