Perl 6 solution, with latest Rakudo (ie built today): 
#         12345678901234567890123456
perl6 -e 'get;say [+]lines.grep: *>0'

[download]

26 character if you don't count the quotes.

Perl 6 - links to (nearly) everything that is Perl 6.

In reply to Re: Counting positive numbers by moritz
in thread Counting positive numbers by Young Monk

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