instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
OXdSmcKG, XbDdSmJl
answer:
dSm


question:
bSBuJiZniSlZtO, AcuJiZniSRAOAv
answer:
uJiZniS


question:
EXqjoANrEDVUsgeCIIIpVkj, piyFjoANrEDVUsuwVbFcJ
answer:

joANrEDVUs