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

[Q]: xfZYYDKEqoRRu, ztCeYYDKEqoPG
[A]: YYDKEqo

[Q]: wbdHVigIkjNkuAmbr, iSgIkjNkQYyn
[A]: gIkjNk

[Q]: hDmAOQLofS, UCTmAOQSCTp
[A]:
mAOQ