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

[Q]: QvtDqzQiSknPbRCG, hVxHdqzQiSknPbumdpNIf
[A]: qzQiSknPb


[Q]: apGMPThLTCw, LvMPThYW
[A]: MPTh


[Q]: AhxuGckaxWpcyq, CskaxWpcXWEVWH
[A]:
kaxWpc