It would be better to use the "uniq" function of List::Util

Beware List::Util::uniq() with numbers.
There's no problem with the integer values being thrown about in this thread, but uniq looks at the stringified values, and there are large numbers of floating point values (including many that represent large integer values) that are unequivalent, yet stringify to the same string:

use warnings;
use List::Util qw(uniq uniqnum);

$x = sqrt 2.0;

# Create $y with a less precise
# approximation of sqrt 2

$y = "$x" + 0;

#$y != $x

print "unequivalent\n" if $x != $y;

# But $x and $y both stringify
# to 1.4142135623731, hence:

$count = uniq($x, $y);
print $count;

__END__

# Outputs:
unequivalent
1
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Using uniqnum instead of uniq yields a value of 2 for $count .
If you want to weed out duplicate strings, use uniq or uniqstr .
But if you want to safely weed out duplicate numeric values, use uniqnum ... and, even then, use only the uniqnum implementation that comes with List::Util-1.55 or later.
(Actually, there might be other modules that now implement a uniqnum function correctly .... I haven't checked.)

Cheers,
Rob