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

SOLUTION: CjAWPH

PROBLEM: NwmTIZSnlKGG, qAYIZSnfWRd

SOLUTION: IZSn

PROBLEM: ktABEFESAVHZkkY, uMjxiESAVHZkZgWUte

SOLUTION:
ESAVHZk