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

Q: YCAyruPTTHWhCYaiXfIl, OETdzqAyruPTTHWgS

A: AyruPTTHW
****
Q: oXZmCSdFrMumlZcP, eFpOZmCSdFrIuHeS

A: ZmCSdFr
****
Q: kVeiUu, vveiVj

A:
ei
****