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

NUuLSmDjCKcJPc, lGGSLIDjCKcJBo
DjCKcJ

fREVIdeTcakgFnwDWTVev, IbtXImseeTcakgFnwDYsKBAlux
eTcakgFnwD

hbIuEPqHtKKDbjGmqQfQta, UtCejRWpHtKKDbjGQrGxKA

HtKKDbjG