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

Q: iYuUgULgqcAgd, kRNUgULgqFv

A: UgULgq
****
Q: NUuLSmDjCKcJPc, lGGSLIDjCKcJBo

A: DjCKcJ
****
Q: TyFCqsKxBagmJCeHc, GtZzJjfFCqsKxBagbsDa

A:
FCqsKxBag
****