In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
--------
Question: TTagIJmzrOTdnKr, UONmtdHJmzrOTduWo

Answer: JmzrOTd


Question: JqdTDnZqSuSVcMsx, TEtDDnZqSuZa

Answer: DnZqSu


Question: YWEnfnfETFuU, cucedSnfnfETFYVIyC

Answer:
nfnfETF