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

SOLUTION: RxEV

PROBLEM: DwkTGsIXLfmjMV, VqRlMxtsSBkTGsIXLfmjbvI

SOLUTION: kTGsIXLfmj

PROBLEM: htBfloSX, YCzBflUp

SOLUTION:
Bfl