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

jsXHot, gtXHmB
XH

nuwMzarLqoPvabJla, JKcrLqoPvabJNDCILGQ
rLqoPvabJ

ikctFShyIrkEOOAprNfmuKY, qQKgXhyIrkEOOAab

hyIrkEOOA