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

Q: KJswoapnXz, EQswoaFyH

A: swoa
****
Q: esIMEOgV, tNIMEybb

A: IME
****
Q: XHifcFnSEHdxz, KDtFnSEHgM

A:
FnSEH
****