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

Q: bdCOjNchdKtvWzOI, FwejNchdKhEd

A: jNchdK
****
Q: plSfJAktMfac, TCjYJAktlt

A: JAkt
****
Q: BmDnesQgPiDAQY, FqEIhesQgPYcbjF

A:
esQgP
****