class Array
  def evens
    get_only :even
  end

  def odds
    get_only :odd
  end


  def get_only(type)
    temp=[]

    type = (type == :even) ? 0 : 1

    self.each_index do |x|
      if((x & 1)==type)
        temp << self[x]
      end
    end
    return temp
  end

end