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: kvutZfcPKzHE, kTKutZfcPTGmU

Answer: utZfcP


Question: PQCjJwXurLeN, vsjJwXuOy

Answer: jJwXu


Question: EWDUQiyuMaE, yMCmhJUQiyuMBeYiOb

Answer:
UQiyuM