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: eMDNXl, ZZDNAa

Answer: DN


Question: yRhCObvPZYoKUoQnyaatR, NHzLJYPZYoKUoQnJnIsZxC

Answer: PZYoKUoQn


Question: oLFwHYnYnhpIluL, gfRefXHYnYnhpJsh

Answer:
HYnYnhp