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: MvALRGKkpALcKdhTtnm, neMkRGKkpALcKdcaxnXEPxW

Answer: RGKkpALcKd


Question: zqwhMdAdXQfQCAmVNaYZm, toYMIwQeadAdXQfQCAmLyheFOv

Answer: dAdXQfQCAm


Question: btyXNbXbTwbTOkDw, BfnXNbXbTwbTOMMafe

Answer:
XNbXbTwbTO