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: OjQHcFUCflYUptUPqYKVomn, GXHcFUCflYUpSSTrQ

Answer: HcFUCflYUp


Question: bmsrkXGb, GcarkXOZF

Answer: rkX


Question: JXyTSEuf, BbLTSEHs

Answer:
TSE