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: YRNpKFPGzUsgCOBJgbVG, TdEpMngFPGzUsgCOZykYRrLp

Answer: FPGzUsgCO


Question: OhMVLbQhBxEaOZY, iDVLbQhBxBiiD

Answer: VLbQhBx


Question: IfLnpZPjJekBwIP, ygZPjJekBNbvxdX

Answer:
ZPjJekB