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

SOLUTION: FwDorPbNP

PROBLEM: pJqqIW, Ivqqxw

SOLUTION: qq

PROBLEM: MJtZXCJFd, mZAAtZXCYdH

SOLUTION:
tZXC