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

OBzHWjmkcgVGPyv, gCHWjmkcgVMq
HWjmkcgV

dlzequypR, Puequqv
equ

jJoZQPZQto, AsZQPZkV

ZQPZ