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

Q: SIIPePlrkftKkzfgdjg, JqNnXHrkftKkzOMUwmc

A: rkftKkz
****
Q: xeKSiBafhOWBbYwlGaQ, GUfIsKgafhOWBbYiFWnptAt

A: afhOWBbY
****
Q: TGafxKbQTUfEgTnqZAH, WJgSKbQTUfEgTnDCk

A:
KbQTUfEgTn
****