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

Q: biAihydBoNlzR, IAloNhydBolwUz

A: hydBo
****
Q: QqtCFzXHPNFXx, XECFzXHPSGwUuk

A: CFzXHP
****
Q: XtKwLWHNi, ikNwLWBa

A:
wLW
****