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

[Q]: FNVeaFmprNHqqtAaKv, iGBmrrMveaFmprNHqWWAvtht
[A]: eaFmprNHq


[Q]: UtUSmsOI, dCUSmGoQ
[A]: USm


[Q]: wASatXUJxjPjwMRiQG, FePNsyiUJxjPjwJYm
[A]:
UJxjPjw