my @g = split;

Careful there - you just allowed stuff like this invalid ISBM through - ISBN 0--06----096975-1. Perhaps you should use: 

my @g = split / /;

[download]

btw, this is valid: ISBN 0-06-096975-X (note the 'X').

-- Dan

In reply to (z) Re^2: CGI -Perl problem by zigdon
in thread Validating ISBN numbers? by gant

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