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: BfCCzPNLBbwCoxMVAG, vhwNLBbwCbH

Answer: NLBbwC


Question: DZfOjrQffR, CXOjrQQc

Answer: OjrQ


Question: XERzMr, ZURzEi

Answer:
Rz