In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Q: CUlMsvov, iflMsSRp

A: lMs
****
Q: IVnbnqBqdPcXfHotUzCYoaGQy, PAlyypBRRBqdPcXfHotpZs

A: BqdPcXfHot
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Q: xAAfbUXukx, dpsfbUXuwTvK

A:
fbUXu
****