#!/usr/bin/perl

use strict;
use warnings;
use diagnostics;
use List::Util qw(min);

my $opt_x = 0;  # Original code allows hex or decimal

my @list = (1, 2, 3, 6, 9, 10, 13, 22, 20, 19, 15, 21);

my %Count;
$Count{$_}++ foreach @list;

my $number;

foreach $number (sort numerically keys(%Count))
{
    my $count = $Count{$number};

    if ($count > 1)
    {
        printf "Token value %d occurs %d times.\n",
                $number, $count if (!$opt_x);
        printf "Token value 0x%x occurs %d times.\n",
                $number, $count if ( $opt_x);
    }
}

# Print a list of the form:
# 100,102,104,108-110,112-115,119

my $expected = min(@list);
my $in_list=0;
my $list_start=0;
my $comma="";

foreach $number (sort numerically keys(%Count))
{
    if (($number == $expected) && ($in_list))
    {
        # Accumulate list
        $in_list++;
    }
    elsif (($number == $expected) && ($in_list == 0))
    {
        $list_start=$number;
        $in_list = 1;
    }
    elsif ($in_list > 1)        # not expected
    {
        printf "%s%d-%d",
                $comma, $list_start, $expected-1
                if (!$opt_x);
        printf "%s0x%x-0x%x",
                $comma, $list_start, $expected-1
                if ( $opt_x);
        $comma = ",";
        $list_start = $number;
        $in_list = 1;
    }
    else        # in_list == 1 and not expected
    {
        printf "%s%d",   $comma, $list_start if (!$opt_x);
        printf "%s0x%x", $comma, $list_start if ( $opt_x);
        $comma = ",";
        $list_start = $number;
        $in_list = 1;
    }

    $expected = $number + 1;
}

if ($in_list > 1)       # Terminate
{
    printf "%s%d-%d",
            $comma, $list_start, $expected-1
            if (!$opt_x);
    printf "%s0x%x-0x%x",
            $comma, $list_start, $expected-1
            if ( $opt_x);
}
elsif ($in_list)
{
    printf "%s%d",   $comma, $list_start if (!$opt_x);
    printf "%s0x%x", $comma, $list_start if ( $opt_x);
}
else
{
    printf "%s%d",   $comma, $number if (!$opt_x);
    printf "%s0x%x", $comma, $number if ( $opt_x);
}
print "\n";


sub numerically { return $a <=> $b; }

exit 0;