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

SOLUTION: QTIa

PROBLEM: qczzCr, zDzzUI

SOLUTION: zz

PROBLEM: BZjDzMXydpXGeDzSuWZFYQHHRAoA, LRfgHTVdpXGeDzSuWmVW

SOLUTION:
dpXGeDzSuW