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

[EX Q]: CxosNa, ikosdx
[EX A]: os

[EX Q]: dZJWBGoeoMepPoTg, pekBGoeoMeQP
[EX A]: BGoeoMe

[EX Q]: LAweyPtjezdcnwrxHPc, gBvQVjezdcnwrzI
[EX A]:
jezdcnwr