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

SOLUTION: bg

PROBLEM: oZZUNCUHtIiauDxQ, OdindZUNCUHtIiLQmWJJf

SOLUTION: ZUNCUHtIi

PROBLEM: PIbVLuHuPlrxTCM, dYLuHuPlrxJMlk

SOLUTION:
LuHuPlrx