In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
--------
Question: faHRBWyXsYzYmHQyy, aHTyXsYzYeXBFV

Answer: yXsYzY


Question: SeXNqRAbKdLuWXgb, npsIWRAbKdLuUWSbvuS

Answer: RAbKdLu


Question: mXaokRXLyqxDmWUByeCCrVlAs, jUTVotrinfLyqxDmWUByahPHUVvRCd

Answer:
LyqxDmWUBy