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: skZGHS, HsZGge

Answer: ZG


Question: mjCEUoPmeKbvCgUtUL, SrHtrPmeKbvYpQAVp

Answer: PmeKbv


Question: ktCNxah, uvUCNxVj

Answer:
CNx