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: MriFNpGM, yaiFNduk

Answer: iFN

Question: zqRbqwgmqGIAGTeeoGFOSr, RFnLqwgmqGIAGLcEvAWxY

Answer: qwgmqGIAG

Question: LbkeCxraEvrZVytWfMQEF, eQkaEvrZVytaCHnhX

Answer:
aEvrZVyt