instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
JqdTDnZqSuSVcMsx, TEtDDnZqSuZa
answer:
DnZqSu


question:
oHoJrr, YAoJSq
answer:
oJ


question:
pyVqjsuKnaBvxoml, mCfGjsuKnazu
answer:

jsuKna