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

ptVlCwpfOZIi, QEdyVlCwpfOwp
VlCwpfO

wXGerDNhSNnCCedyzskswVnh, BfFNhSNnCCedybrUbI
NhSNnCCedy

yuWdFV, bJWdjV

Wd