instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
OezHeoe, ouUzHemU
answer:
zHe


question:
yRhCObvPZYoKUoQnyaatR, NHzLJYPZYoKUoQnJnIsZxC
answer:
PZYoKUoQn


question:
ZaCsmRIg, dqDCsmxM
answer:

Csm