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

SOLUTION: NzngllN

PROBLEM: yOGvgtAmwMwcIRtJ, cQtAmwMwcIRjfjO

SOLUTION: tAmwMwcIR

PROBLEM: oAvMjnDXCaNkPlp, ApwlgtvMjnDXCaNkGC

SOLUTION:
vMjnDXCaNk