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

Q: fCGEhfHvcRouHzNw, gtjBkhfHvcRouHee

A: hfHvcRouH
****
Q: mJoHBJehHtkFS, ZMrDxHBJehHtxS

A: HBJehHt
****
Q: BiKceDPPkltIggzIdCXHMBc, rMmbFvPPkltIggzIRDKER

A:
PPkltIggzI
****