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Решение на Трета задача от Изабела Недялкова

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Резултати

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

Код

class Expr
def self.build(tree)
first, *rest = *tree
rest.map! { |item| item.is_a?(Array) ? build(item) : item }
case first
when :number then Number.new(rest.last)
when :variable then Variable.new(rest.last)
when :+ then Addition.new(rest)
when :* then Multiplication.new(rest)
when :- then Negation.new(rest.last)
when :sin then Sine.new(rest.last)
when :cos then Cosine.new(rest.last)
end
end
end
class Unary < Expr
attr_accessor :argument
def initialize(argument)
@argument = argument
end
def argument_simplified
@argument_simplified ||= @argument.simplify
end
def ==(other)
self.class == other.class && @argument == other.argument
end
def exact?
@argument.exact?
end
def simplify
self
end
end
class Binary < Expr
attr_accessor :left
attr_accessor :right
def initialize(argument)
@left, @right = *argument
end
def left_simplified
@left_simplified ||= @left.simplify
end
def right_simplified
@right_simplified ||= @right.simplify
end
def ==(other)
self.class == other.class && @left == other.left && @right == other.right
end
def exact?
@left.exact? && @right.exact?
end
end
class Number < Unary
def evaluate(environment = {})
@argument
end
def exact?
true
end
def derive(variable)
Number.new(0).simplify
end
end
class Addition < Binary
def evaluate(environment = {})
@left.evaluate(environment) + @right.evaluate(environment)
end
def simplify
if right_simplified == Number.new(0)
left_simplified
elsif left_simplified == Number.new(0)
right_simplified
elsif @left.exact? && @right.exact?
Number.new(evaluate(environment = {}))
else
self
end
end
def derive(variable)
Addition.new([@left.derive(variable), @right.derive(variable)]).simplify
end
end
class Multiplication < Binary
def evaluate(environment = {})
left.evaluate(environment) * right.evaluate(environment)
end
def simplify
if right_simplified == Number.new(0) || left_simplified == Number.new(0)
Number.new(0)
elsif right_simplified == Number.new(1)
left_simplified
elsif left_simplified == Number.new(1)
right_simplified
elsif @left.exact? && @right.exact?
Number.new(evaluate(environment = {}))
else
self
end
end
def derive(variable)
Addition.new([Multiplication.new([@left.derive(variable), @right]).simplify,
Multiplication.new([@left, @right.derive(variable)]).simplify])
end
end
class Variable < Unary
def evaluate(environment = {})
if environment[@argument]
environment[@argument]
else
fail
end
end
def exact?
false
end
def derive(variable)
if variable == @argument
Number.new(1).simplify
else
Number.new(0).simplify
end
end
end
class Negation < Unary
def evaluate(environment = {})
-@argument.evaluate(environment)
end
end
class Sine < Unary
def evaluate(environment = {})
Math.sin(@argument.evaluate(environment))
end
def simplify
if argument_simplified == Number.new(0)
Number.new(0)
elsif @argument.exact?
evaluate(environment = {})
else
self
end
end
def derive(variable)
Multiplication.new([@argument.derive(variable), Cosine.new(@argument)]).simplify
end
end
class Cosine < Unary
def evaluate(environment = {})
Math.cos(@argument.evaluate(environment))
end
def simplify
if argument_simplified == Number.new(1)
Number.new(0)
elsif @argument.exact?
evaluate(environment = {})
else
self
end
end
def derive(variable)
Multiplication.new([@argument.derive(variable), Negation.new(Sine.new(@argument))]).simplify
end
end

Лог от изпълнението

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Finished in 0.04938 seconds
13 examples, 0 failures

История (3 версии и 0 коментара)

Изабела обнови решението на 13.11.2012 01:59 (преди около 12 години)

+class Expr
+ def self.build(sexp)
+ first, *rest = *sexp
+ rest.map! { |item| item.is_a?(Array) ? build(item) : item }
+ case first
+ when :number then Number.new(rest.last)
+ when :variable then Variable.new(rest.last)
+ when :+ then Addition.new(rest)
+ when :* then Multiplication.new(rest)
+ when :- then Negation.new(rest.last)
+ when :sin then Sine.new(rest.last)
+ when :cos then Cosine.new(rest.last)
+ end
+ end
+end
+
+class Unary < Expr
+ attr_accessor :argument
+
+ def initialize(argument)
+ @argument = argument
+ end
+
+ def argument_simplified
+ @argument_simplified ||= @argument.simplify
+ end
+
+ def ==(other)
+ self.class == other.class && @argument == other.argument
+ end
+
+ def exact?
+ @argument.exact?
+ end
+
+ def simplify
+ self
+ end
+end
+
+class Binary < Expr
+ attr_accessor :left
+ attr_accessor :right
+
+ def initialize(argument)
+ @left, @right = *argument
+ end
+
+ def left_simplified
+ @left_simplified ||= @left.simplify
+ end
+
+ def right_simplified
+ @right_simplified ||= @right.simplify
+ end
+
+ def ==(other)
+ self.class == other.class && @left == other.left && @right == other.right
+ end
+
+ def exact?
+ @left.exact? && @right.exact?
+ end
+end
+
+class Number < Unary
+ def evaluate(environment = {})
+ @argument
+ end
+
+ def exact?
+ true
+ end
+
+ def derive(variable)
+ Number.new(0).simplify
+ end
+end
+
+class Addition < Binary
+ def evaluate(environment = {})
+ @left.evaluate(environment) + @right.evaluate(environment)
+ end
+
+ def simplify
+ if right_simplified == Number.new(0)
+ left_simplified
+ elsif left_simplified == Number.new(0)
+ right_simplified
+ elsif @left.exact? && @right.exact?
+ Number.new(evaluate(environment = {}))
+ else
+ self
+ end
+ end
+
+ def derive(variable)
+ Addition.new([@left.derive(variable), @right.derive(variable)]).simplify
+ end
+end
+
+class Multiplication < Binary
+ def evaluate(environment = {})
+ left.evaluate(environment) * right.evaluate(environment)
+ end
+
+ def simplify
+ if right_simplified == Number.new(0) || left_simplified == Number.new(0)
+ Number.new(0)
+ elsif right_simplified == Number.new(1)
+ left_simplified
+ elsif left_simplified == Number.new(1)
+ right_simplified
+ elsif @left.exact? && @right.exact?
+ Number.new(evaluate(environment = {}))
+ else
+ self
+ end
+ end
+
+ def derive(variable)
+ Addition.new([Multiplication.new([@left.derive(variable), @right]).simplify,
+ Multiplication.new([@left, @right.derive(variable)]).simplify])
+ end
+end
+
+class Variable < Unary
+ def evaluate(environment = {})
+ environment[@argument] ||= fail
+ end
+
+ def exact?
+ false
+ end
+
+ def derive(variable)
+ if variable == @argument
+ Number.new(1).simplify
+ else
+ Number.new(0).simplify
+ end
+ end
+end
+
+class Negation < Unary
+ def evaluate(environment = {})
+ -@argument.evaluate(environment)
+ end
+end
+
+class Sine < Unary
+ def evaluate(environment = {})
+ Math.sin(@argument.evaluate(environment))
+ end
+
+ def simplify
+ if argument_simplified == Number.new(0)
+ Number.new(0)
+ elsif @argument.exact?
+ evaluate(environment = {})
+ else
+ self
+ end
+ end
+
+ def derive(variable)
+ Multiplication.new([@argument.derive(variable), Cosine.new(@argument)]).simplify
+ end
+end
+
+class Cosine < Unary
+ def evaluate(environment = {})
+ Math.cos(@argument.evaluate(environment))
+ end
+
+ def simplify
+ if argument_simplified == Number.new(1)
+ Number.new(0)
+ elsif @argument.exact?
+ evaluate(environment = {})
+ else
+ self
+ end
+ end
+
+ def derive(variable)
+ Multiplication.new([@argument.derive(variable), Negation.new(Sine.new(@argument))]).simplify
+ end
+end

Изабела обнови решението на 13.11.2012 03:00 (преди около 12 години)

class Expr
def self.build(sexp)
first, *rest = *sexp
rest.map! { |item| item.is_a?(Array) ? build(item) : item }
case first
when :number then Number.new(rest.last)
when :variable then Variable.new(rest.last)
when :+ then Addition.new(rest)
when :* then Multiplication.new(rest)
when :- then Negation.new(rest.last)
when :sin then Sine.new(rest.last)
when :cos then Cosine.new(rest.last)
end
end
end
class Unary < Expr
attr_accessor :argument
def initialize(argument)
@argument = argument
end
def argument_simplified
@argument_simplified ||= @argument.simplify
end
def ==(other)
self.class == other.class && @argument == other.argument
end
def exact?
@argument.exact?
end
def simplify
self
end
end
class Binary < Expr
attr_accessor :left
attr_accessor :right
def initialize(argument)
@left, @right = *argument
end
def left_simplified
@left_simplified ||= @left.simplify
end
def right_simplified
@right_simplified ||= @right.simplify
end
def ==(other)
self.class == other.class && @left == other.left && @right == other.right
end
def exact?
@left.exact? && @right.exact?
end
end
class Number < Unary
def evaluate(environment = {})
@argument
end
def exact?
true
end
def derive(variable)
Number.new(0).simplify
end
end
class Addition < Binary
def evaluate(environment = {})
@left.evaluate(environment) + @right.evaluate(environment)
end
def simplify
if right_simplified == Number.new(0)
left_simplified
elsif left_simplified == Number.new(0)
right_simplified
elsif @left.exact? && @right.exact?
Number.new(evaluate(environment = {}))
else
self
end
end
def derive(variable)
Addition.new([@left.derive(variable), @right.derive(variable)]).simplify
end
end
class Multiplication < Binary
def evaluate(environment = {})
left.evaluate(environment) * right.evaluate(environment)
end
def simplify
if right_simplified == Number.new(0) || left_simplified == Number.new(0)
Number.new(0)
elsif right_simplified == Number.new(1)
left_simplified
elsif left_simplified == Number.new(1)
right_simplified
elsif @left.exact? && @right.exact?
Number.new(evaluate(environment = {}))
else
self
end
end
def derive(variable)
Addition.new([Multiplication.new([@left.derive(variable), @right]).simplify,
Multiplication.new([@left, @right.derive(variable)]).simplify])
end
end
class Variable < Unary
def evaluate(environment = {})
- environment[@argument] ||= fail
+ if environment[@argument]
+ environment[@argument]
+ else
+ fail
+ end
end
def exact?
false
end
def derive(variable)
if variable == @argument
Number.new(1).simplify
else
Number.new(0).simplify
end
end
end
class Negation < Unary
def evaluate(environment = {})
-@argument.evaluate(environment)
end
end
class Sine < Unary
def evaluate(environment = {})
Math.sin(@argument.evaluate(environment))
end
def simplify
if argument_simplified == Number.new(0)
Number.new(0)
elsif @argument.exact?
evaluate(environment = {})
else
self
end
end
def derive(variable)
Multiplication.new([@argument.derive(variable), Cosine.new(@argument)]).simplify
end
end
class Cosine < Unary
def evaluate(environment = {})
Math.cos(@argument.evaluate(environment))
end
def simplify
if argument_simplified == Number.new(1)
Number.new(0)
elsif @argument.exact?
evaluate(environment = {})
else
self
end
end
def derive(variable)
Multiplication.new([@argument.derive(variable), Negation.new(Sine.new(@argument))]).simplify
end
end

Изабела обнови решението на 13.11.2012 13:36 (преди около 12 години)

class Expr
- def self.build(sexp)
- first, *rest = *sexp
+ def self.build(tree)
+ first, *rest = *tree
rest.map! { |item| item.is_a?(Array) ? build(item) : item }
case first
when :number then Number.new(rest.last)
when :variable then Variable.new(rest.last)
when :+ then Addition.new(rest)
when :* then Multiplication.new(rest)
when :- then Negation.new(rest.last)
when :sin then Sine.new(rest.last)
when :cos then Cosine.new(rest.last)
end
end
end
class Unary < Expr
attr_accessor :argument
def initialize(argument)
@argument = argument
end
def argument_simplified
@argument_simplified ||= @argument.simplify
end
def ==(other)
self.class == other.class && @argument == other.argument
end
def exact?
@argument.exact?
end
def simplify
self
end
end
class Binary < Expr
attr_accessor :left
attr_accessor :right
def initialize(argument)
@left, @right = *argument
end
def left_simplified
@left_simplified ||= @left.simplify
end
def right_simplified
@right_simplified ||= @right.simplify
end
def ==(other)
self.class == other.class && @left == other.left && @right == other.right
end
def exact?
@left.exact? && @right.exact?
end
end
class Number < Unary
def evaluate(environment = {})
@argument
end
def exact?
true
end
def derive(variable)
Number.new(0).simplify
end
end
class Addition < Binary
def evaluate(environment = {})
@left.evaluate(environment) + @right.evaluate(environment)
end
def simplify
if right_simplified == Number.new(0)
left_simplified
elsif left_simplified == Number.new(0)
right_simplified
elsif @left.exact? && @right.exact?
Number.new(evaluate(environment = {}))
else
self
end
end
def derive(variable)
Addition.new([@left.derive(variable), @right.derive(variable)]).simplify
end
end
class Multiplication < Binary
def evaluate(environment = {})
left.evaluate(environment) * right.evaluate(environment)
end
def simplify
if right_simplified == Number.new(0) || left_simplified == Number.new(0)
Number.new(0)
elsif right_simplified == Number.new(1)
left_simplified
elsif left_simplified == Number.new(1)
right_simplified
elsif @left.exact? && @right.exact?
Number.new(evaluate(environment = {}))
else
self
end
end
def derive(variable)
Addition.new([Multiplication.new([@left.derive(variable), @right]).simplify,
Multiplication.new([@left, @right.derive(variable)]).simplify])
end
end
class Variable < Unary
def evaluate(environment = {})
if environment[@argument]
environment[@argument]
else
fail
end
end
def exact?
false
end
def derive(variable)
if variable == @argument
Number.new(1).simplify
else
Number.new(0).simplify
end
end
end
class Negation < Unary
def evaluate(environment = {})
-@argument.evaluate(environment)
end
end
class Sine < Unary
def evaluate(environment = {})
Math.sin(@argument.evaluate(environment))
end
def simplify
if argument_simplified == Number.new(0)
Number.new(0)
elsif @argument.exact?
evaluate(environment = {})
else
self
end
end
def derive(variable)
Multiplication.new([@argument.derive(variable), Cosine.new(@argument)]).simplify
end
end
class Cosine < Unary
def evaluate(environment = {})
Math.cos(@argument.evaluate(environment))
end
def simplify
if argument_simplified == Number.new(1)
Number.new(0)
elsif @argument.exact?
evaluate(environment = {})
else
self
end
end
def derive(variable)
Multiplication.new([@argument.derive(variable), Negation.new(Sine.new(@argument))]).simplify
end
end