From Chris Pine's Learn to Program: Orange tree. Make an OrangeTree class that has a height method that returns its height and a one_year_passes method that, when called, ages the tree one year. Each year the tree grows taller (however much you think an orange tree should grow in a year), and after some number of years (again, your call) the tre…

orangetree.rb

class OrangeTree
  def initialize 
    @age = 0
    @height = 0
    @orange_count = 0
    @alive = true
  end
  
  def height
    if @alive
      @height
    else
      'A dead tree isn\'t very tall. :('
    end
  end
  
  def count_the_oranges
    if @alive
      @orange_count
    else
      "Dead trees don't have fruit..."
    end
  end
  
  def pick_an_orange
    if @alive
      if @orange_count == 1
        @orange_count = @orange_count - 1
        puts "You just ate the last delicious orange on this tree. There are 0 oranges left."
      elsif @orange_count > 1
        puts "You just ate a delicious orange."
        @orange_count = @orange_count - 1
        puts "There are #{@orange_count} oranges left to eat."
      else
        puts "Sorry, there aren't any oranges on this tree."
      end
    else
      "Dead trees don't produce fruit, sorry bud."
    end
  end
    
  def one_year_passes
    
    if @alive 
      if @height < 40
        @age = @age + 1 # tree ages tree one year
        @orange_count = 0 # all the oranges fall off
        @height = @height + rand(5) #tree grows taller/height increases
        if @age > 4
          grow_fruit
        end
        puts "This year your tree is #{@height} feet tall, and has #{@orange_count} oranges. It is #{@age} years old."
      elsif @height >= 40 && rand(3) > 1
        @alive = false
        puts "Your tree just died, son."
      end
    else
      "Your tree is still dead one year later."
    end
  end
  
  def has_fruit?
    if @alive
      if @orange_count > 0 
        true
      else 
        false
      end
    else
      false
    end
  end
  
  def grow_fruit
    if @alive 
      if @age <= 6 #between 4 and 6
        @orange_count = @orange_count + 10
      end
      if @age > 6 && @age < 10 #between 7 and 9
        @orange_count = @orange_count + 20
      end
      if @age >=10 && @age < 40 #between 10 and whatever
        @orange_count = @orange_count + 30
      end
    else
      @orange_count = 0
    end
  end
end

ot = OrangeTree.new 
23.times do
  ot.one_year_passes
  ot.pick_an_orange
end