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

SOLUTION: HWjmkcgV

PROBLEM: sUdaWtsiRgqAYHykrHwjyDvZgD, MJdFXYiRgqAYHykrakSGHMr

SOLUTION: iRgqAYHykr

PROBLEM: zhQMqFOZBejNCnPBfdG, JkkdqFOZBejNCnAlHog

SOLUTION:
qFOZBejNCn