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

Q: slTUxy, oqTUYa

A: TU
****
Q: wkVVZREWhcSCpvCTB, ZQWhcSCpvCDVUY

A: WhcSCpvC
****
Q: FoCARMQbdROqAtABblAEGGbByM, JZCQbdROqAtABkBumbi

A:
QbdROqAtAB
****