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

[Q]: ztkWLUJQXxP, fYluOkWLUJKDX
[A]: kWLUJ


[Q]: ZKMRTxCxbsbX, iovHrMRTxCxbsjv
[A]: MRTxCxbs


[Q]: ZXEmxyDwg, PamxyDAQT
[A]:
mxyD