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

SOLUTION: LZd

PROBLEM: eJPZzg, lFPZbI

SOLUTION: PZ

PROBLEM: JojWBt, tvjWLF

SOLUTION:
jW