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

SJIkEibGrqcrOBgGjYjJc, EervOGrqcrOBgGJZyx
GrqcrOBgG

rRmkmETbjzCzZZxihrVdefxfcenJ, ogQtzAgWjKCzZZxihrVdRswMCmngp
CzZZxihrVd

PyAjniohBNBbDcm, RtAZxtniohBNUEwNY

niohBN