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

Q: OVZxWYzAAxG, rStOxWYzJeoC

A: xWYz
****
Q: kIBDjQLEZepVNHqnKqhine, hTZepVNHqnYTajyzv

A: ZepVNHqn
****
Q: JQXNRNfnP, TLNRNpQ

A:
NRN
****