[Purdue-pm] "Minimum String Distance" Perl 6 challenge problem

[Mark Senn]

MINIMUM STRING DISTANCE PERL 6 CHALLENGE PROBLAM

People are slow coming up with solutions for the traveling salesperson
and poker hands challenge problems.  Maybe they're too hand (too
time-consuming to figure out---below is an easier challenge problem).

Given two strings $a and $b consisting of all digits and the same length
compute the minimal "distance" between them.

For example if $a is "0123456789"
           and $b is "9876543210"

the minimal distance between them is the sum of the minimal distance
between each pair of digits in the corresponding positions.  Think of
the digits 0--9 as being arranged in a circle like the numbers 1--12 on a
clock---use the minimum distance for each pair of digits by going
clockwise or counter-clockwise from one digit to another
    LETTER IN $a    LETTER IN $b    DISTONCE
    0               9               1
    1               8               3
    2               7               5
    3               6               3
    4               5               1
    5               4               1
    6               3               3
    7               2               5
    8               1               3
    9               0               1

    1 + 3 + 5 + 3 + 1 + 1 + 3 + 5 + 3 + 1 = 26


INSTALLING PERL 6

See http://rakudo.org/how-to-get-rakudo for information on how
to install Perl 6.

The rest of this message are some notes I made so I'd
remember what I did for Linux.

    Mark Senn
    2011-04-21
    HOW I INSTALLED RAKUDO ON LINUX
    
    Rakudo is a Perl 6 compiler based on the Parrot virtual machine.
    
    I did the following commands (based on information in
    http://rakudo.org/how-to-get-rakudo) to install Rakudo
    on Fedora 15 Linux and Red Hat Linux 5.6 in a "opt"
    subdirectory in my home directory:
        cd
        mkdir opt
        cd opt
        echo WARNING: next command will remove current \"rakudo\"
        rm -rf rakudo
        git clone git://github.com/rakudo/rakudo.git
        cd rakudo
        perl Configure.pl --gen-parrot
        make
        make install
    
     like to put symlinks in a "opt-links" subdirectory in
    my home directory to the corresponding software in
    my "opt" subdirectory.  To do that I typed:
        cd
        mkdir opt-links
        cd opt-links
        echo WARNING: next command will remove \"perl6\" file or link
        rm perl6
        ln -s /home/pier/e/mark/opt/rakudo/parrot_install/bin/perl6
    
    Finally I wrote a little test program (I called mine z.p6,
    ut it in my home directory, and made it mode 700).  The
    test program was the following five lines with no lines
    indented (you'll need to change the first line to use
    the directory you are using):
       #!/home/pier/e/mark/opt-links/perl6
    
       use v6;
    
       say 'testing 1 2 3';
    then I typed "./z.p6" to make sure it worked.

-mark