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

Q: GoodBOwvrki, kRCsdBOwvrakgiH

A: dBOwvr
****
Q: IQIHqbEhpVuNATp, GIJIHqbEhpzWb

A: IHqbEhp
****
Q: czAYSy, SqAYby

A:
AY
****