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

[Q]: iYuUgULgqcAgd, kRNUgULgqFv
[A]: UgULgq


[Q]: QaxEaxdouNyyvNAn, wRjWSaxdouNyyrriQiG
[A]: axdouNyy


[Q]: BfwVvutuPuS, yfEycvutuPeeu
[A]:
vutuP


