TASK DEFINITION: In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
PROBLEM: bUHPpvVtFQNSpUdg, zggEFoKBHPpvVtFQNHXsc

SOLUTION: HPpvVtFQN

PROBLEM: DnAzbgMtdPKsNCMpBfc, QdfXRkWREzbgMtdPKsGx

SOLUTION: zbgMtdPKs

PROBLEM: CsmDeVxSkk, fXGmDeVxYtgqG

SOLUTION:
mDeVx