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

Q: LiiFMMLGfNHVnnga, beXMMLGfNHVsjdfdN

A: MMLGfNHV
****
Q: AuSFmN, crSFXM

A: SF
****
Q: bGrzuCZwfhDnAosQtESdOeemX, hxhDnAosQtEnQCxxEwF

A:
hDnAosQtE
****