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

[Q]: zgJGhxLU, EwJGhedW
[A]: JGh


[Q]: CuizrSvJTRWZK, udyrSvJTRZzkS
[A]: rSvJTR


[Q]: OmzPpiuxHHUXScOk, OVnrvIuxHHUXzOMkF
[A]:
uxHHUX


