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

[Q]: vhZuXCsIkQR, YflCuXCsIkLu
[A]: uXCsIk


[Q]: ATmVEtUuZOgsBUuL, UMUuZOgsBPVT
[A]: UuZOgsB


[Q]: GwwevMFSAvf, PLaevMFGr
[A]:
evMF