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

[Q]: wNiHcaiUPHnjp, aSTmjcaiUPHFzOu
[A]: caiUPH


[Q]: yPODMimvyQPYWHfcM, aZiotMimvyQPZncH
[A]: MimvyQP


[Q]: QXhQVJyDtbVPbxrA, DZLInDlQVJyDtbVQs
[A]:
QVJyDtbV