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

Q: fREVIdeTcakgFnwDWTVev, IbtXImseeTcakgFnwDYsKBAlux

A: eTcakgFnwD
****
Q: ksRxEVrz, cOMRxEViwF

A: RxEV
****
Q: DsrWRpxexvjFONLiMy, hyrWRpxexvjFucqtsG

A:
rWRpxexvjF
****