instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
GHdeqnuYnQ, zzQeqnutAZ
answer:
eqnu


question:
oZZUNCUHtIiauDxQ, OdindZUNCUHtIiLQmWJJf
answer:
ZUNCUHtIi


question:
SyoIHvFuGmMoEWtuyWdDp, XLTmQMOoIHvFuGmMory
answer:

oIHvFuGmMo