diff options
| -rw-r--r-- | challenge-169/dave-jacoby/perl/ch-1.pl | 53 | ||||
| -rw-r--r-- | challenge-169/dave-jacoby/perl/ch-2.pl | 71 |
2 files changed, 124 insertions, 0 deletions
diff --git a/challenge-169/dave-jacoby/perl/ch-1.pl b/challenge-169/dave-jacoby/perl/ch-1.pl new file mode 100644 index 0000000000..5d6764590c --- /dev/null +++ b/challenge-169/dave-jacoby/perl/ch-1.pl @@ -0,0 +1,53 @@ +#!/usr/bin/env perl + +use strict; +use warnings; +use experimental qw{ say postderef signatures state }; + +my $iter = make_iterator(2); +my @brilliant; + +while ( my $i = $iter->() ) { + push @brilliant, $i if is_brilliant($i); + last if scalar @brilliant >= 20; +} +say join ', ', @brilliant; + +sub is_brilliant( $n ) { + my @factors = get_factors($n); + + # two prime factors + return 0 unless scalar @factors == 2; + + # same length + return 0 unless length $factors[0] == length $factors[1]; + return 1; +} + +sub is_prime ($n) { + die "Bad number $n" unless length $n; + return 0 if $n == 0; + return 0 if $n == 1; + for ( 2 .. sqrt $n ) { return 0 unless $n % $_ } + return 1; +} + +sub get_factors( $n ) { + my @factors; + for my $i ( 2 .. $n ) { + next unless $n % $i == 0; + while ( $n % $i == 0 ) { + push @factors, $i; + $n = $n / $i; + } + } + return @factors; +} + +sub make_iterator($n) { + return sub { + state $v = $n; + return $v++; + } +} + diff --git a/challenge-169/dave-jacoby/perl/ch-2.pl b/challenge-169/dave-jacoby/perl/ch-2.pl new file mode 100644 index 0000000000..8c31e12b8f --- /dev/null +++ b/challenge-169/dave-jacoby/perl/ch-2.pl @@ -0,0 +1,71 @@ +#!/usr/bin/env perl + +use strict; +use warnings; +use experimental qw{ say postderef signatures state }; + +my $iter = make_iterator(2); +my @achilles; + +while ( my $i = $iter->() ) { + next if is_achilles($i) == 0; + push @achilles, $i; + last if scalar @achilles >= 20; +} + +say join ', ', @achilles; +exit; + +sub is_achilles( $n ) { + return 0 if is_prime($n); + return 0 if !is_powerful($n); + return 0 if is_perfect($n); + return 1; +} + +sub is_perfect( $n ) { + for my $i ( 2 .. $n ) { + my $j = $n**( 1 / $i ); + return 1 if ( $j =~ /^-?\d+$/ ) ; + } + return 0; +} + +sub is_powerful($n) { + my @factors = get_factors($n); + my %factors; + map { $factors{$_}++ } @factors; + for my $f ( keys %factors ) { + return 0 if $factors{$f} < 2; + } + return 1; + +} + +sub is_prime ($n) { + die "Bad number $n" unless length $n; + return 0 if $n == 0; + return 0 if $n == 1; + for ( 2 .. sqrt $n ) { return 0 unless $n % $_ } + return 1; +} + +sub get_factors( $n ) { + my @factors; + for my $i ( 2 .. $n ) { + next unless $n % $i == 0; + while ( $n % $i == 0 ) { + push @factors, $i; + $n = $n / $i; + } + } + return @factors; +} + +sub make_iterator($n) { + return sub { + state $v = $n; + return $v++; + } +} + |
