TITLE

AUTHOR

Write a program or a script that returns the last Fridays of each month
of a given year. The year may be given through any simple input method
in your language (command line, std in, etc.).


head

L<http://rosettacode.org/wiki/Last_Fridays#Raku>


The MAIN sub - L<https://doc.perl6.org/language/functions#sub_MAIN>


Date objects - L<https://doc.perl6.org/type/Date>


code

=begin code :lang<raku>
use v6;



sub MAIN (Int $year = Date.today.year) {
    my @fri;
    for Date.new("$year-01-01") .. Date.new("$year-12-31") {
        @fri[.month] = .Str if .day-of-week == 5;
    }
    .say for @fri[1..12];
}

# vim: expandtab shiftwidth=4 ft=perl6

=end code


root

100 Doors


100-doors.pl

24 game


24-game.pl

Accumulator factory


accumulator-factory.pl

Ackermann function


ackermann-function.pl

Arbitrary-precision integers (included)


arbitrary-precision-integers.pl

Balanced brackets


balanced-brackets.pl

Binomial Coefficient


binomial-coefficient.pl

Copy a string


copy-a-string.pl

Create a two-dimensional array at runtime


create-a-two-dimensional-array-at-runtime.pl

Hailstone sequence


hailstone-sequence.pl

Prime decomposition


prime-decomposition.pl

README.md

para

L<Examples| file:../examples/index.podlite>


L<Download |file:../download/index.podlite>


React

=begin React :component<HeaderCol> :id<menu> 
=para L<Documentation|/doc/introduction>
=para L<Modules| /mods>
=para L<Examples| file:../examples/index.podlite>
=para L<Download |file:../download/index.podlite>
=para L<About|file:../about/index.podlite>
=para 🔍 K<⌘K>/K<ctrl-K>
=end React


HEADER

FOOTER

Last fridays of the year


The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.


Example: 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}


Write a function which returns an array or collection which contains the
prime decomposition of a given number, n, greater than 1. If your language
does not have an isPrime-like function available, you may assume that you
have a function which determines whether a number is prime (note its name
before your code).


L<http://rosettacode.org/wiki/Prime_decomposition#Raku>


=begin code :lang<raku>
use v6;



my @primes = 2, 3, 5, -> $n is copy {
    repeat { $n += 2 } until $n %% none @primes ... { $_ * $_ >= $n }
    $n;
} ... *;

sub factors(Int $remainder is copy) {
    return 1 if $remainder <= 1;
    gather for @primes -> $factor {
        if $factor * $factor > $remainder {
            take $remainder if $remainder > 1;
            last;
        }

        # How many times can we divide by this prime?
        while $remainder %% $factor {
            take $factor;
            last if ($remainder div= $factor) === 1;
        }
    }
}

say "{factors 536870911}";

# vim: expandtab shiftwidth=4 ft=perl6

=end code


last-fridays-of-year.pl

The Hailstone sequence of numbers can be generated from a starting positive
integer, n by:


* If n is 1 then the sequence ends.
* If n is even then the next n of the sequence = n/2
* If n is odd then the next n of the sequence = (3 * n) + 1


The (unproven), Collatz conjecture is that the hailstone sequence for any
starting number always terminates.


Create a routine to generate the hailstone sequence for a number.


Use the routine to show that the hailstone sequence for the number 27 has 112
elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1


Show the number less than 100,000 which has the longest hailstone sequence
together with that sequence's length.


U<http://rosettacode.org/wiki/Hailstone_sequence#Raku>


=begin code :lang<raku>
use v6;



sub hailstone($n) { $n, { $_ %% 2 ?? $_ div 2 !! $_ * 3 + 1 } ... 1 }

my @h = hailstone(27);
say "Length of hailstone(27) = {+@h}";
say ~@h;

my $m max= +hailstone($_) => $_ for 1..99_999;
say "Max length $m.key() was found for hailstone($m.value()) for numbers < 100_000";


# vim: expandtab shiftwidth=4 ft=perl6

=end code


The Raku Knowledge Base


=begin React :component<HeaderCol> :id<footer>  
=begin nested :!nested
=item1 B<Language>
    =item2 L<Get started|file:../getting-started/getting-started.podlite>
    =item2 L<Why Raku?|/doc/language/faq#Why-should-I-learn-Raku-What's-so-great-about-it>
    =item2 L<Try Raku|https://glot.io/new/raku>
    =item2 L<Raku cheat sheet|https://github.com/Raku/mu/blob/master/docs/Perl6/Cheatsheet/cheatsheet.txt>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<Raku on Exercism|https://exercism.org/tracks/raku>
    =item2 L<Wikipedia|https://en.wikipedia.org/wiki/Raku_(programming_language)>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>

=end nested
=begin nested :!nested

=item1 B<L<Documentation|/doc>>
    =item2 L<Getting started, Migration guides from other languages, & Tutorials | file:../doc/introduction.podlite>
    =item2 L<Language References|file:../doc/reference.podlite>
    =item2 L<Type Reference| file:../doc/types.podlite>
    =item2 L<Miscellaneous| file:../doc/miscellaneous.podlite>
    =item2 L<FAQs (Frequently Asked Questions)|/doc/language/faq>
    =item2 L<Community|/doc/language/community>
    =item2 L<The list of all documents|file:../doc/index.podlite>

=item1 B<Resources>
    =item2 L<The Raku Guide|https://raku.guide/>
    =item2 L<Books |https://perl6book.com/>
    =item2 L<Rosetta Code | https://www.raku.org/community/rosettacode>

=end nested
=begin nested :!nested

=item1 B<Resoures>
    =item2 L<Download | file:../download/index.podlite>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>

=item1 B<Learning>
    =item2 L<The Raku Guide|https://raku.guide/>
    =item2 L<Wikibook |https://en.wikibooks.org/wiki/Raku_Programming>
    =item2 L<Books |https://perl6book.com/>
    =item2 L<Rosetta Code | https://www.raku.org/community/rosettacode>
    =item2 L<Learn Raku in Y minutes|https://learnxinyminutes.com/docs/raku/>
    =item2 L<Golfing |https://github.com/AlexDaniel/raku-golf-cheatsheet>
=end nested
=begin nested :!nested

=item1 B<Explore>
    =item2 L<Raku Blog Aggregator|https://planet.raku.org/>
    =item2 L<Rakudo Weekly|https://rakudoweekly.blog/>
    =item2 L<The Weekly Challenge |https://perlweeklychallenge.org/>
    =item2 L<Raku Advent Calendar|https://raku-advent.blog/>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>

=end nested
=end React


=begin React :component<CookieConsent> :id<CookieConsent> :buttonCaption("Got it!")
=para
This website uses cookies for analytics.
=end React


Last fridays of the year

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