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

SOLUTION: RAbKdLu

PROBLEM: cUCQXEFSgRZjK, RYdvUQXEFSgRZVlwx

SOLUTION: QXEFSgRZ

PROBLEM: zwdEOlzXscWS, KvOlzXwn

SOLUTION:
OlzX