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: NNpkdhvgT, BMkAkdhvrwV

Answer: kdhv


Question: jeQzwP, kSQzxq

Answer: Qz


Question: qJBgkUmiggUur, ungkUmiKtNd

Answer:
gkUmi