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

SOLUTION: kTGsIXLfmj

PROBLEM: biAihydBoNlzR, IAloNhydBolwUz

SOLUTION: hydBo

PROBLEM: bQnzVgLkEsrCx, DnxqVgLkEtfZW

SOLUTION:
VgLkE