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: rEHxRBOktYreNkK, NCOktYreFFCFwi

Answer: OktYre

Question: NwmTIZSnlKGG, qAYIZSnfWRd

Answer: IZSn

Question: HhbZfWsjADLu, ylfWsjhh

Answer:
fWsj