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

SOLUTION: SuVu

PROBLEM: eeoJEtGHPDvHck, ezPGHPDvHSf

SOLUTION: GHPDvH

PROBLEM: fIOurDFyqqOO, tQEgurDFyCZ

SOLUTION:
urDFy