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

SOLUTION: ZG

PROBLEM: UldKHMpUYADGfEUGcSon, nPHMpUYADGfEKqHCLPmL

SOLUTION: HMpUYADGfE

PROBLEM: ZNeTyvONg, UYUeTyvIjv

SOLUTION:
eTyv