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: BVipiZoGXaWdjmDsxWP, yxppsiYkiZoGXaWdjoDRuKW

Answer: iZoGXaWdj


Question: kUoqCMPFTqGE, guoqCMPkwJs

Answer: oqCMP


Question: BkWwMM, HXWwxv

Answer:
Ww