instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
mXHhaCEIwqwEZcz, JZPXbYHhaCEIwZmna
answer:
HhaCEIw


question:
CUlMsvov, iflMsSRp
answer:
lMs


question:
LQBiFNozMrSGziAoH, TsNozMrSGgjXL
answer:

NozMrSG