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

[Q]: umXfmRnUgALpFAqBaKfNfo, aOAXWnUgALpFAqBmNpTCdj
[A]: nUgALpFAqB


[Q]: AxRSlkQfWHrdlgQG, iXIOrmlkQfWHTy
[A]: lkQfWH


[Q]: PGjDRPDzGaBR, rpIJRPDzWi
[A]:
RPDz