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

Q: jXbgnl, lUbglP

A: bg
****
Q: GFhJafTV, waHhJaji

A: hJa
****
Q: wDSKHtWbCDqTeoBeiYHdcZD, MydQCwqTeoBeiYHdYMp

A:
qTeoBeiYHd
****