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

[Q]: yRhCObvPZYoKUoQnyaatR, NHzLJYPZYoKUoQnJnIsZxC
[A]: PZYoKUoQn


[Q]: OyXwTWbLByC, yODnTWbLWYzc
[A]: TWbL


[Q]: PWNgnRzUnD, FtwuNgnRfVNo
[A]:
NgnR