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

uZSRkFDHsGXNMaggxUn, lTrQKKpsGXNMaggEdSrEX
sGXNMagg

SODsrWUjUBSgA, WIWUjUBCUUs
WUjUB

gLepqYywpKVqMsEd, wlRSywpKVqMsDiVJw

ywpKVqMs