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: zeuyZKwvIOfx, BlmZKwvspUt

Answer: ZKwv


Question: iMwanJBuMdiZDL, kIafHeBuMdiZmKNA

Answer: BuMdiZ


Question: nDNZhlMJyXunKi, sugUEVMJyXungs

Answer:
MJyXun