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: FiKGCRXutEOzMqP, xdxRXutEsl

Answer: RXutE


Question: uqazNuZhdJhw, KbnrzNuZhBdp

Answer: zNuZh


Question: bOvlVNWf, iivlVzWt

Answer:
vlV