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: jkGcUm, dxGcSI

Answer: Gc


Question: wCfNCfxvLRAxBstRTwMSqTn, AhwxfFNCfxvLRAxBrNtf

Answer: NCfxvLRAxB


Question: VgTFCRLK, UnnuTFCRdgw

Answer:
TFCR