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

[EX Q]: zRwQdelc, UdAUwQdejhe
[EX A]: wQde

[EX Q]: PnRypl, HvRydi
[EX A]: Ry

[EX Q]: jpTAYFcp, GOoAYFCxt
[EX A]:
AYF