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

[Q]: txJhzNeBj, qLJhzNesV
[A]: JhzNe


[Q]: ZhHtTXaUmsQfUMNrnt, KvvebSXaUmsQfBspwM
[A]: XaUmsQf


[Q]: eXtKkZDQf, vQBKkZtOh
[A]:
KkZ