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

[Q]: eeoJEtGHPDvHck, ezPGHPDvHSf
[A]: GHPDvH


[Q]: xeKSiBafhOWBbYwlGaQ, GUfIsKgafhOWBbYiFWnptAt
[A]: afhOWBbY


[Q]: VovPsZzoKppVtUhj, sefYUvPsZzoKJNld
[A]:
vPsZzoK