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

mQvintdwLUpClREgxv, rYnoXBtdwLUpClRwxsqX
tdwLUpClR

ATmVEtUuZOgsBUuL, UMUuZOgsBPVT
UuZOgsB

ootgJvIUFQMg, KxLvmtgJvIUTu

tgJvIU