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

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


[Q]: KKrCLvJKRoyV, WDeLvJKCBdS
[A]: LvJK


[Q]: LfGzyEMghJDsqNvGmkRWpdu, XofrUhJDsqNvGurP
[A]:
hJDsqNvG