The publisher-code and serial number facets of an ISBN together occupy eight digits, but individually are of variable length. A prolific publisher has a short publishercode to allow a large range of...

The publisher-code and serial number facets of an ISBN together occupy eight digits, but individually are of variable length. A prolific publisher has a short publishercode to allow a large range of serial numbers; the larger number of low-volume publishers are catered for by giving them long publisher-codes and correspondingly small serial number ranges. What problem does this pose for computer system design and how might it be solved?