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: gwVLygvd, VOQLyglfo

Answer: Lyg


Question: gfDDsblwUryUw, UWaRisblwUTqTM

Answer: sblwU


Question: hGTxXxbHfElvuCNAyUnHQgA, HqkfElvuCNAyUzH

Answer:
fElvuCNAyU