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: sUdaWtsiRgqAYHykrHwjyDvZgD, MJdFXYiRgqAYHykrakSGHMr

Answer: iRgqAYHykr


Question: EyvnjbVLF, vqnjblzR

Answer: njb


Question: jzcuWQ, mtcuHg

Answer:
cu