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

nuwMzarLqoPvabJla, JKcrLqoPvabJNDCILGQ
rLqoPvabJ

WFAPUCgVYbmZiFlacUzyv, xQFiekrgPUCgVYbmZUEtl
PUCgVYbmZ

SBzICgXMCCI, SnSICgXbHX

ICgX