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

SOLUTION: kdhv

PROBLEM: HLtkkRnWkgIdqbQH, dWeFUtkkRnWkgIdZhlQh

SOLUTION: tkkRnWkgId

PROBLEM: cQmbLAEoiIefGEKAR, VINtoiIefGEKpnHiMpfP

SOLUTION:
oiIefGEK