#! perl -slw
use strict;

sub nUniqC{
      my @uniq; ## Updated. 
	@uniq[unpack 'U*',$_[0]] = (1)x length $_[0];
	scalar (grep defined $_, @uniq);
}

print nUniqC '1010101010';
print nUniqC '1234567812';

##</code><code>##

sub nUniqC{
	my @uniq;
	scalar grep{ ++$uniq[$_] == 1 } unpack('C*',$_[0]);
}

##</code><code>##

sub nUniqC{
	scalar grep{ ++$_[$_] == 1 } unpack('C*',$_[0]);
}