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: faHRBWyXsYzYmHQyy, aHTyXsYzYeXBFV

Answer: yXsYzY


Question: yITbYie, TlqTbYomH

Answer: TbY


Question: fFuCaSTwKyveGb, dmsLaSTwKyvxhckuT

Answer:
aSTwKyv