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

KvPFobZEGs, eKFobZEtnm
FobZE

OFbCjZDoRRlLsMU, DcCjZDoRRtld
CjZDoRR

yjKOLdDarFmdJurSsIyFa, VqyjarFmdJurSshQ

arFmdJurSs