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

SOLUTION: bjA

PROBLEM: JjEQVKijeyEQ, dwSVKijeywCTvb

SOLUTION: VKijey

PROBLEM: rABWRmXNrArAPKt, VcjDXNrArAwzA

SOLUTION:
XNrArA