instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
QzJdafaGRLWEguLkOaw, brmPLBoaGRLWEguEaF
answer:
aGRLWEgu


question:
andNlOdIcQMyZvc, vCMENolkslOdIcQMyZJtCFo
answer:
lOdIcQMyZ


question:
XXBYwHsAFyWHrPzVvrmsL, LKdfTBjFyWHrPzVtPbU
answer:

FyWHrPzV