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

qczzCr, zDzzUI
zz

jFVaEHbMrrkW, ekfVaEHbPnBnM
VaEHb

tOGplyblhAjZzkdTOqTe, wlgUJFNDLxGplyblhAjZsEoQV

GplyblhAjZ