instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
rlBoVyFsYqpmmQmelGBg, iKKaIyFsYqpmmWcrKn
answer:
yFsYqpmm


question:
vMsEJRoLkWcmkuwNRz, ZmoLkWcmVZiBv
answer:
oLkWcm


question:
oJIpUUxxPSvO, InFPfpUUxxHYhm
answer:

pUUxx