instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
GnElFKBIoYmAdvz, GrElFKBIoMo
answer:
ElFKBIo


question:
NwmTIZSnlKGG, qAYIZSnfWRd
answer:
IZSn


question:
yZFdbjuAiYpek, IgdbjuAHKr
answer:

dbjuA