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

[Q]: Owbiay, exbime
[A]: bi


[Q]: CiElmOvTqJGVJkfSaDRzE, EjDJwMyxTvTqJGVJkfluB
[A]: vTqJGVJkf


[Q]: ilwFhYgPBzSpsxjryhXe, wyEEBoxrYgPBzSpsHWMFk
[A]:
YgPBzSps