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

[Q]: rvLoiycpZw, idcvoiycpcLyD
[A]: oiycp


[Q]: GFhJafTV, waHhJaji
[A]: hJa


[Q]: DRUNELNZbOOSvJah, qgzNZbOOSvJPNiTIVic
[A]:
NZbOOSvJ