As you can read in Search and replace in perlretut, substitution returns the number of substitutions, so that is what you are passing to print.

As an example, 

#!/usr/bin/perl
use strict;
use warnings;

my $string = 'I like cats.  I think cats are nice.';
print $string =~ s/cat/dog/g;

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In reply to Re: Inline substitution regex by kennethk
in thread Inline substitution regex by bradcan

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