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

Q: JjEQVKijeyEQ, dwSVKijeywCTvb

A: VKijey
****
Q: YHLJZrFQ, aSLJZQuo

A: LJZ
****
Q: KwtRZTJL, RBuRZTcGA

A:
RZT
****