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

[Q]: sEYtoQlG, XIstoQQPw
[A]: toQ


[Q]: tWJoKSOAuVhmsomA, emdmnBFJoKSOAuVzSgW
[A]: JoKSOAuV


[Q]: TAfXpoI, PNfXpBZy
[A]:
fXp