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: fREVIdeTcakgFnwDWTVev, IbtXImseeTcakgFnwDYsKBAlux

Answer: eTcakgFnwD


Question: PivhPfah, XSghPfOi

Answer: hPf


Question: AFPaOOktYZuGYP, jGFTPaOOktLEwc

Answer:
PaOOkt