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

[Q]: ZRjPgqbLL, uIsmPgqbBB
[A]: Pgqb


[Q]: OgWFOfjNYmXVjBBvOdunIc, eGljKGnzFKFOfjNYmXVjdlqsT
[A]: FOfjNYmXVj


[Q]: OebKSsUOHw, eaGAKSsUONDDM
[A]:
KSsUO