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: EyvnjbVLF, vqnjblzR

Answer: njb


Question: BfCCzPNLBbwCoxMVAG, vhwNLBbwCbH

Answer: NLBbwC


Question: bfpRkPVVIp, gWTkPVVqPr

Answer:
kPVV