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

UQDJDbzqDxsMzUL, BxClJDbzqDxLxlngc
JDbzqDx

lkFGXvTkKm, wwELXvTkcOnG
XvTk

DKgUVMV, KhgUVgG

gUV