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

jsXHot, gtXHmB
XH

haOsaSQcyodWhqQaC, BKLEUQcyodWhvVkmxBz
QcyodWh

PquDCZveORmCEyOiLdzIg, miCZveORmCEyRkftu

CZveORmCEy