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: skZGHS, HsZGge

Answer: ZG


Question: pdlvGFDoaycPSKDBelS, BRaycPSKDBPCNaKCy

Answer:
aycPSKDB