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

Q: cvZfWOwa, xOfWOhZs

A: fWO
****
Q: VLxrvK, gvxrac

A: xr
****
Q: rVdHETymDPEVVwIg, MRTpjhETymDPTDU

A:
ETymDP
****