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: mOGzbnDXWnNurkBXtcqZ, NLahGzbnDXWnNYgMTOR

Answer: GzbnDXWnN


Question: jJSSBmflUyrEMLjSycA, YkmujkSSBmflUyrKKJZ

Answer: SSBmflUyr


Question: oXHDyfVsz, XpDHDyfqZ

Answer:
HDyf