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

sHndIbPaygfNvnquxIHeteW, huLmJWXZIgfNvnquxIViQDhbuoL
gfNvnquxI

dsngGP, KvnglB
ng

WqMEtLYhCmUXCibmhiN, AIZJMEtLYhCmUWP

MEtLYhCmU