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

wXGerDNhSNnCCedyzskswVnh, BfFNhSNnCCedybrUbI
NhSNnCCedy

HXYkGv, GCYksu
Yk

rgdfItuwSaqvcLgueS, WSNnItuwSaqdWXSY

ItuwSaq