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

Q: OUNqomxFcLXhWdfB, gdqomxFcLHQPCu

A: qomxFcL
****
Q: gTjTwC, OUjTgM

A: jT
****
Q: lGSboYDZvnIzf, VBISboYDZvtL

A:
SboYDZv
****