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

SOLUTION: MEDTXnE

PROBLEM: slTUxy, oqTUYa

SOLUTION: TU

PROBLEM: eAQeoFcOd, TLGeoFcWCmE

SOLUTION:
eoFc