instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
QEEVsnbQIgrxaZmflaZ, dPSbljkdQIgrxaZmgVzMT
answer:
QIgrxaZm


question:
vJtmxQmHEq, yobgAtmxQmMeoLz
answer:
tmxQm


question:
wbdHVigIkjNkuAmbr, iSgIkjNkQYyn
answer:

gIkjNk