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

SOLUTION: JMpx

PROBLEM: UZbmGVDzIaf, qfHwqGVDzIsd

SOLUTION: GVDzI

PROBLEM: uLnvGAyRGp, dkcnvGAyRUA

SOLUTION:
nvGAyR