instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
yjoJzBGdwfOhsceoOpoap, uSLMdBGdwfOhsIQHBijd
answer:
BGdwfOhs


question:
DFRoMPNDAzNgtLsEPseOzC, qykyPjDAzNgtLsEPYTsNrJaNK
answer:
DAzNgtLsEP


question:
GJtXeEuLXn, rHEBXeEuLtju
answer:

XeEuL