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

Q: sJRFPufsaWXNeu, AePufsafc

A: Pufsa
****
Q: rduIwWNGM, AJqYIwWNaCap

A: IwWN
****
Q: sypJSUtCzcQ, vEJSUtzZiZ

A:
JSUt
****