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

Q: oCtWZYdkvZ, pkktWZYdEHMW

A: tWZYd
****
Q: eNuawupVqQ, RIawuplUIf

A: awup
****
Q: cgffBIALhlnVUWshV, qTLIQffBIALhlnTTHw

A:
ffBIALhln
****