I am a newcomer to Perl (and to programming in general; I just finished the Llama book) and someone recommended that I work through the problems on the http://www.streamtech.nl/site/problem+set website by way of practice. This is my attempt at the first problem. It produces the correct output, so I'd just like to know if there's any style issues or other bad practices in my code that I should know about:

#!/usr/bin/perl
use warnings;
use strict;
use 5.010;

# The 3n + 1 problem (http://www.streamtech.nl/problemset/100.html)

my ( $first, $second, $cycle_length );
my $max_cycle_length = 0;

say "Input:";
chomp( my @pairs = <> );

say "Output:";
foreach my $pair (@pairs) {
    ( $first, $second ) = split( / /, $pair );

    foreach my $num ( $first .. $second ) {
        $cycle_length = totalizer($num);
        if ( $cycle_length > $max_cycle_length ) {
            $max_cycle_length = $cycle_length;
        }
    }
    say "$first $second $max_cycle_length";
}

sub totalizer {
    my $number = shift;
    $cycle_length = 0;
    {
        ++$cycle_length;
        last if ( $number == 1 );

        if ( $number % 2 != 0 ) {
            $number = ( $number * 3 + 1 );
        }
        else {
            $number = $number / 2;
        }
        redo;
    }
    return $cycle_length;
}

[download]

The Wisdom of the Monks will be most welcome.

In reply to General style advice requested by iangibson

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.