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: trHTzJpm, aCHTzVVA

Answer: HTz


Question: wkVVZREWhcSCpvCTB, ZQWhcSCpvCDVUY

Answer: WhcSCpvC


Question: ubQjTaFsORGeKu, XhkTaFsOuV

Answer:
TaFsO