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: XqyPjqNZDEK, EfwPjqNgjIP

Answer: PjqN

Question: kyADtWLlnmYv, tcaKvDtWLlnvBq

Answer: DtWLln

Question: NRdneuWdAN, bmGIeuWdXsh

Answer:
euWd