In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Q: BrDGrTD, PBHDGrDw

A: DGr
****
Q: PQSFjlnU, kTSFjMUh

A: SFj
****
Q: UbsxnWgazAWa, IgsdlnWgazioaEq

A:
nWgaz
****