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

uGDJixAmSiVaFRmfKRM, NsTGxsJixAmSiVageSw
JixAmSiVa

XeQwOS, OuQwNR
Qw

lnxAcTKOvqmRvqGozwU, NjQkGbYPhtKOvqmRvqGowdMDYQ

KOvqmRvqGo