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

[Q]: BrDGrTD, PBHDGrDw
[A]: DGr


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


[Q]: InblhwbKOtAom, awhwbKObUTe
[A]:
hwbKO


