instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
OhMVLbQhBxEaOZY, iDVLbQhBxBiiD
answer:
VLbQhBx


question:
mvIvSzMtYsfVLdaGEmef, wnzMtYsfVLdaKm
answer:
zMtYsfVLda


question:
hKArEtjrTkexX, luRArEtjriQJX
answer:

ArEtjr