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

SOLUTION: gfNvnquxI

PROBLEM: PzXzvmYrlGZgOBk, iKnzvmYrlGZgOrs

SOLUTION: zvmYrlGZgO

PROBLEM: SEkvxJlPN, hRkvxJluAhr

SOLUTION:
kvxJl