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

LJJvLTK, jpFJvLqh
JvL

mRVieYomZqJXaTDsShCyfPW, ifOAlnptmZqJXaTDsVMqY
mZqJXaTDs

GhbsUaeYowJhEQluaCqe, PsHdtwoYowJhEQlyHJS

YowJhEQl