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

[Q]: RNYHvcNnbsUdJLvS, PpNnbsUdglWhl
[A]: NnbsUd


[Q]: QECPAHsg, bUfPAHOWb
[A]: PAH


[Q]: rvnkMieTA, tOkMiGbV
[A]:
kMi