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: BrDGrTD, PBHDGrDw

Answer: DGr


Question: AedXEOrEgvnzF, TVTEOrEgvxKuJgv

Answer: EOrEgv


Question: LqKVIpAxevTGDPJ, lHKVIpAxevTAarN

Answer:
KVIpAxevT