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

SOLUTION: RkfCFZGOy

PROBLEM: MvALRGKkpALcKdhTtnm, neMkRGKkpALcKdcaxnXEPxW

SOLUTION: RGKkpALcKd

PROBLEM: TEhhebpAYK, IbgebpAoakV

SOLUTION:
ebpA