instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
fAsWQxuyBevvLogrSrgg, tmdBEUxuyBevvLogXjiMCbh
answer:
xuyBevvLog


question:
krnkpodgfpCKtfCqyzUbymWbxi, DydgSWpCKtfCqyzDaMsjqc
answer:
pCKtfCqyz


question:
jjZPUiM, AfZPULT
answer:

ZPU