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Решение на Втора задача от Емил Гоцев

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Резултати

  • 6 точки от тестове
  • 0 бонус точки
  • 6 точки общо
  • 11 успешни тест(а)
  • 0 неуспешни тест(а)

Код

class Song
attr_accessor :name, :artist, :album
def initialize(name, artist, album)
@name = name
@artist = artist
@album = album
end
end
class Collection
attr_accessor :songs
include Enumerable
def initialize
@songs = []
end
def each
@songs.each { |song| yield song }
end
def Collection.parse(text)
new_collection = Collection.new
text.split(/\n+/).each_slice(3) do |slice|
new_collection.songs << Song.new(slice[0], slice[1], slice[2])
end
new_collection
end
def artists
map { |song| song.artist }.uniq
end
def albums
map { |song| song.album }.uniq
end
def names
map { |song| song.name }.uniq
end
def filter(criteria)
new_collection = Collection.new
new_collection.songs = select { |song| criteria.match? song }
new_collection
end
def adjoin(collection)
adjoined = Collection.new
adjoined.songs = self.songs | collection.songs
adjoined
end
end
class Criteria
def initialize(filter_string)
@filter_string = filter_string
end
def self.name(filter_string)
NameCriteria.new(filter_string)
end
def self.artist(filter_string)
ArtistCriteria.new(filter_string)
end
def self.album(filter_string)
AlbumCriteria.new(filter_string)
end
def &(other)
DoubleCriteria.new(self, other, :and)
end
def |(other)
DoubleCriteria.new(self, other, :or)
end
def !
ReversedCriteria.new(self)
end
end
class DoubleCriteria < Criteria
def initialize(first_criteria, second_criteria, operator)
@first_criteria = first_criteria
@second_criteria = second_criteria
@operator = operator
end
def match?(song)
if @operator == :and
@first_criteria.match?(song) & @second_criteria.match?(song)
elsif @operator == :or
@first_criteria.match?(song) | @second_criteria.match?(song)
end
end
end
class ReversedCriteria < Criteria
def initialize(criteria)
@criteria = criteria
end
def match?(song)
!@criteria.match? song
end
end
class NameCriteria < Criteria
def match?(song)
song.name.eql? @filter_string
end
end
class ArtistCriteria < Criteria
def match?(song)
song.artist.eql? @filter_string
end
end
class AlbumCriteria < Criteria
def match?(song)
song.album.eql? @filter_string
end
end

Лог от изпълнението

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Finished in 0.01022 seconds
11 examples, 0 failures

История (1 версия и 1 коментар)

Емил обнови решението на 31.10.2012 15:50 (преди над 11 години)

+class Song
+ attr_accessor :name, :artist, :album
+
+ def initialize(name, artist, album)
+ @name = name
+ @artist = artist
+ @album = album
+ end
+end
+
+class Collection
+ attr_accessor :songs
+
+ include Enumerable
+
+ def initialize
+ @songs = []
+ end
+
+ def each
+ @songs.each { |song| yield song }
+ end
+
+ def Collection.parse(text)
+ new_collection = Collection.new
+ text.split(/\n+/).each_slice(3) do |slice|
+ new_collection.songs << Song.new(slice[0], slice[1], slice[2])
+ end
+ new_collection
+ end
+
+ def artists
+ map { |song| song.artist }.uniq
+ end
+
+ def albums
+ map { |song| song.album }.uniq
+ end
+
+ def names
+ map { |song| song.name }.uniq
+ end
+
+ def filter(criteria)
+ new_collection = Collection.new
+ new_collection.songs = select { |song| criteria.match? song }
+ new_collection
+ end
+
+ def adjoin(collection)
+ adjoined = Collection.new
+ adjoined.songs = self.songs | collection.songs
+ adjoined
+ end
+end
+
+class Criteria
+ def initialize(filter_string)
+ @filter_string = filter_string
+ end
+
+ def self.name(filter_string)
+ NameCriteria.new(filter_string)
+ end
+
+ def self.artist(filter_string)
+ ArtistCriteria.new(filter_string)
+ end
+
+ def self.album(filter_string)
+ AlbumCriteria.new(filter_string)
+ end
+
+ def &(other)
+ DoubleCriteria.new(self, other, :and)
+ end
+
+ def |(other)
+ DoubleCriteria.new(self, other, :or)
+ end
+
+ def !
+ ReversedCriteria.new(self)
+ end
+end
+
+class DoubleCriteria < Criteria
+ def initialize(first_criteria, second_criteria, operator)
+ @first_criteria = first_criteria
+ @second_criteria = second_criteria
+ @operator = operator
+ end
+
+ def match?(song)
+ if @operator == :and
+ @first_criteria.match?(song) & @second_criteria.match?(song)
+ elsif @operator == :or
+ @first_criteria.match?(song) | @second_criteria.match?(song)
+ end
+ end
+end
+
+class ReversedCriteria < Criteria
+ def initialize(criteria)
+ @criteria = criteria
+ end
+
+ def match?(song)
+ !@criteria.match? song
+ end
+end
+
+class NameCriteria < Criteria
+ def match?(song)
+ song.name.eql? @filter_string
+ end
+end
+
+class ArtistCriteria < Criteria
+ def match?(song)
+ song.artist.eql? @filter_string
+ end
+end
+
+class AlbumCriteria < Criteria
+ def match?(song)
+ song.album.eql? @filter_string
+ end
+end