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

[Q]: fBpRXPkikQokGVeS, FwUbKXkikQokGos
[A]: kikQokG


[Q]: KKrCLvJKRoyV, WDeLvJKCBdS
[A]: LvJK


[Q]: APaBVI, xraBYO
[A]:
aB