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

[EX Q]: ykDpbd, YFDpmO
[EX A]: Dp

[EX Q]: zgJGhxLU, EwJGhedW
[EX A]: JGh

[EX Q]: ExAuKbBgHxRYKwWEG, REyKKbBgHxRuNlesct
[EX A]:
KbBgHxR