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

dReySjyqecU, loSjyqiRl
Sjyq

GlAYDsKQoXy, IxDsKQuK
DsKQ

lYWLFcivzIUdVGIzcNGQb, ceNQniRqTtvzIUdVGIzcsloQNGG

vzIUdVGIzc