- Added solutions by Maxim Nechaev.

3 files changed, 11399 insertions, 0 deletions

diff --git a/challenge-007/maxim-nechaev/perl5/ch-1.pl b/challenge-007/maxim-nechaev/perl5/ch-1.pl
new file mode 100755
index 0000000000..9dd8f1d049
--- /dev/null
+++ b/challenge-007/maxim-nechaev/perl5/ch-1.pl
@@ -0,0 +1,9 @@
+#!/usr/bin/perl -w
+use strict;
+use List::Util qw/sum/;
+
+my @nivens = grep {
+    $_ and not $_ % sum split //;
+} 0..50;
+
+print join("\n", @nivens), "\n";
diff --git a/challenge-007/maxim-nechaev/perl5/ch-2.pl b/challenge-007/maxim-nechaev/perl5/ch-2.pl
new file mode 100755
index 0000000000..e230d75317
--- /dev/null
+++ b/challenge-007/maxim-nechaev/perl5/ch-2.pl
@@ -0,0 +1,31 @@
+#!/usr/bin/perl -w
+use strict;
+use Graph::Undirected;
+use Algorithm::Combinatorics qw/combinations/;
+
+sub find_shortest_ladder
+{
+    my ($word1, $word2, $words) = @_;
+
+    my $g = Graph::Undirected->new;
+    map { $g->add_vertex($_) } @$words;
+
+    my $len = length($words->[0]) - 1;
+    my $iter = combinations($words, 2);
+    while( my $pair = $iter->next ) {
+	my $diffs = 0;
+	foreach my $i (0..$len) {
+	    $diffs++ if substr($pair->[0], $i, 1) ne substr($pair->[1], $i, 1);
+	    last if $diffs == 2;
+	}
+	$g->add_edge( @$pair ) if $diffs == 1;
+    }
+    return $g->SP_Dijkstra($word1, $word2);
+}
+
+
+$ARGV[0] || die "use: $0 filename_dict";
+my @words = <>;
+@words = map { chomp; $_ } @words;
+my @ladder = find_shortest_ladder('water', 'bread', \@words);
+print join("\n", @ladder), "\n";
diff --git a/challenge-007/maxim-nechaev/perl5/words.txt b/challenge-007/maxim-nechaev/perl5/words.txt
new file mode 100755
index 0000000000..6a3aac463e
--- /dev/null
+++ b/challenge-007/maxim-nechaev/perl5/words.txt
@@ -0,0 +1,11359 @@
+aahed
+aalii
+aargh
+abaca
+abaci
+aback
+abacs
+abaft
+abaka
+aband
+abase
+abash
+abask
+abate
+abaya
+abbas
+abbey
+abbot
+abbés
+abeam
+abear
+abele
+abets
+abhor
+abide
+abies
+abled
+abler
+ables
+ablet
+ablow
+abmho
+abode
+abohm
+aboil
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+aboon
+abord
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+abort
+about
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+acold
+acorn
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+acres
+acrid
+acron
+acted
+actin
+acton
+actor
+acute
+acyls
+adage
+adapt
+adays
+addax
+added
+adder
+addio
+addle
+adeem
+adept
+adieu
+adits
+adiós
+adman
+admen
+admit
+admix
+adobe
+adobo
+adopt
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+adorn
+adown
+adoze
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+adred
+adsum
+adult
+adunc
+adust
+advew
+adyta
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+adzes
+aecia
+aedes
+aegis
+aeons
+aerie
+aesir
+afara
+afars
+afear
+affix
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+aflaj
+afoot
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+afoul
+afrit
+afros
+after
+again
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+agamy
+agape
+agars
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+agate
+agave
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+agene
+agent
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+agger
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+aggro
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+agile
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