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

Q: OYERnjubLFovtcS, FngzQJVGERnjubLFafmzq

A: ERnjubLF
****
Q: rduIwWNGM, AJqYIwWNaCap

A: IwWN
****
Q: TeaARKlgJNass, XxXMRKlgJPxfrn

A:
RKlgJ
****