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

SOLUTION: ty

PROBLEM: zqwhMdAdXQfQCAmVNaYZm, toYMIwQeadAdXQfQCAmLyheFOv

SOLUTION: dAdXQfQCAm

PROBLEM: naOsumkFB, KHSOsumArNi

SOLUTION:
Osum