In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

[Q]: ktABEFESAVHZkkY, uMjxiESAVHZkZgWUte
[A]: ESAVHZk


[Q]: SIIPePlrkftKkzfgdjg, JqNnXHrkftKkzOMUwmc
[A]: rkftKkz


[Q]: BalNmbsCGK, FYllNmbZuj
[A]:
lNmb