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: JqdTDnZqSuSVcMsx, TEtDDnZqSuZa

Answer: DnZqSu


Question: UiaECWZf, gRyaECWLGRl

Answer: aECW


Question: fLRGBGRLbLeKUfCrdDrP, tcRGBGRLbLebQq

Answer:
RGBGRLbLe