Greetings all,

In working with a series of numbers representing page numbers of a manual, I found that I prefered to read something like, "1-3, 5, 7-9, 11" instead of "1, 2, 3, 5, 7, 8, 9, 11" most of the time. So I immediately set out to make a Perl-thing to do just that. However, as most things I write, the first version works, but isn't the most efficient code around:

use strict;

my @array = (1, 2, 3, 5, 7, 8, 9, 11, 14);
my @new_array;

# If it works: @new_array = ('1-3', 5, '7-9', 11, 14);

my $x = 0;
my $y = 0;

while ($x <= $#array) {
    $new_array[$y] = $array[$x];

    if ($array[$x] + 1 == $array[$x+1]) {
        while ($array[$x] + 1 == $array[$x+1]) { $x++ }
        $new_array[$y] .= "-$array[$x]";
    }

    $x++;
    $y++;
}

print join(', ', @new_array), "\n";

[download]

As far as I've tested this, it seems to work. However, I'd like it to be better in two very important ways. First, there's got to be a simpler, faster way to do this. Second, is there an easy way to handle letters? For example, the "A, C-F, L..." sort of thing. Thanks in advance for your help.

-gryphon

In reply to Humanized lists of numbers by gryphon

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