rpcfn13.out

1.  The country with the highest population (1,210,004,956 people) is China.

2.  Top 5 countries sorted by inflation rate:
    Belarus - 244%
    Turkey - 94%
    Azerbaijan - 85%
    Malawi - 83.3%
    Yemen - 71.3%

3a. 6 continents found in factbook:
    Africa
    Asia
    Australia/Oceania
    Europe
    North America
    South America

3b. 260 countries found in factbook listed alphabetically by country:

EUROPE(49): Albania, Andorra, Austria, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Faroe Islands, Finland, France, Germany, Gibraltar, Greece, Guernsey, Holy See, Hungary, Iceland, Ireland, Italy, Jan Mayen, Jersey, Latvia, Liechtenstein, Lithuania, Luxembourg, Macedonia, Malta, Man, Moldova, Monaco, Netherlands, Norway, Poland, Portugal, Romania, San Marino, Serbia and Montenegro, Slovakia, Slovenia, Spain, Svalbard, Sweden, Switzerland, Ukraine, United Kingdom 

AFRICA(65): Algeria, Angola, Bassas da India, Benin, Botswana, Bouvet Island, Burkina Faso, Burundi, Cameroon, Cape Verde, Central African Republic, Chad, Comoros, Congo, Cote dIvoire, Djibouti, Egypt, Equatorial Guinea, Eritrea, Ethiopia, Europa Island, French Southern and Antarctic Lands, Gabon, Gambia, Ghana, Glorioso Islands, Guinea, Guinea-Bissau, Heard Island and McDonald Islands, Juan de Nova Island, Kenya, Lesotho, Liberia, Libya, Madagascar, Malawi, Mali, Mauritania, Mauritius, Mayotte, Morocco, Mozambique, Namibia, Niger, Nigeria, Reunion, Rwanda, Saint Helena, Sao Tome and Principe, Senegal, Seychelles, Sierra Leone, Somalia, South Africa, Sudan, Swaziland, Tanzania, Togo, Tromelin Island, Tunisia, Uganda, Western Sahara, Zaire, Zambia, Zimbabwe 

SOUTH AMERICA(15): Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands, French Guiana, Guyana, Paraguay, Peru, South Georgia and the South Sandwich Islands, Suriname, Uruguay, Venezuela 

AUSTRALIA/OCEANIA(33): American Samoa, Australia, Baker Island, Cook Islands, Coral Sea Islands, Fiji, French Polynesia, Guam, Howland Island, Jarvis Island, Johnston Atoll, Kingman Reef, Kiribati, Marshall Islands, Micronesia, Midway Islands, Nauru, New Caledonia, New Zealand, Niue, Norfolk Island, Northern Mariana Islands, Palau, Palmyra Atoll, Pitcairn Islands, Solomon Islands, Tokelau, Tonga, Tuvalu, Vanuatu, Wake Island, Wallis and Futuna, Western Samoa 

NORTH AMERICA(39): Anguilla, Antigua and Barbuda, Aruba, Bahamas, Barbados, Belize, Bermuda, British Virgin Islands, Canada, Cayman Islands, Clipperton Island, Costa Rica, Cuba, Dominica, Dominican Republic, El Salvador, Greenland, Grenada, Guadeloupe, Guatemala, Haiti, Honduras, Jamaica, Martinique, Mexico, Montserrat, Navassa Island, Netherlands Antilles, Nicaragua, Panama, Puerto Rico, Saint Kitts and Nevis, Saint Lucia, Saint Pierre and Miquelon, Saint Vincent and the Grenadines, Trinidad and Tobago, Turks and Caicos Islands, United States, Virgin Islands 

ASIA(59): Afghanistan, Armenia, Ashmore and Cartier Islands, Azerbaijan, Bahrain, Bangladesh, Bhutan, British Indian Ocean Territory, Brunei, Burma, Cambodia, China, Christmas Island, Cocos Islands, Cyprus, Gaza Strip, Georgia, Hong Kong, India, Indonesia, Iran, Iraq, Israel, Japan, Jordan, Kazakstan, Kuwait, Kyrgyzstan, Laos, Lebanon, Macau, Malaysia, Maldives, Mongolia, Nepal, North Korea, Oman, Pakistan, Papua New Guinea, Paracel Islands, Philippines, Qatar, Russia, Saudi Arabia, Singapore, South Korea, Spratly Islands, Sri Lanka, Syria, Taiwan, Tajikistan, Thailand, Turkey, Turkmenistan, United Arab Emirates, Uzbekistan, Vietnam, West Bank, Yemen 

rpcfn13.rb

class Factbook
  require "rexml/document"

  def initialize(book)
    file = File.new(book)
    doc = REXML::Document.new file
    @world = {}
    @continents = doc.root.elements.to_a("//continent").sort! { |a,b| a.attributes["name"] <=> b.attributes["name"] }
    @countries = doc.root.elements.to_a("//country")
  end

  def find_country_with_highest_population
    country_name, population = "", 0
    @countries.each do |country|
      if country.attributes["population"].to_i > population
        country_name, population = country.attributes["name"], country.attributes["population"].to_i
      end
    end
    puts "1.  The country with the highest population (#{number_with_delimiter(population)} people) is #{country_name}."
  end

  def find_top_5_countries_by_inflation_rate
    @countries.sort! { |a,b| b.attributes["inflation"].to_f <=> a.attributes["inflation"].to_f }
    puts "\n2.  Top 5 countries sorted by inflation rate:"
    @countries[0..4].each do |country|
      puts "    #{country.attributes["name"]} - #{country.attributes["inflation"]}%"
    end
  end

  def list_continents
    puts "\n3a. #{@continents.count.to_s} continents found in factbook:"
    @continents.each { |continent| puts "    #{continent.attributes["name"]}" }
  end
  
  def list_countries_by_continent
    order_countries
    puts "\n3b. #{@countries.count.to_s} countries found in factbook listed alphabetically by country:\n\n" 
    @world.each_pair { |continent, countries| very_pretty_print(continent,countries) }
  end

  private
  
  def number_with_delimiter(number, delimiter=",")
    number.to_s.gsub(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1#{delimiter}")
  end

  def order_countries
    @continents.each do |continent|      
      temp_continent = []
      @countries.each do |country|
        if country.attributes["continent"] == continent.attributes["name"] 
          temp_continent << country.attributes["name"] 
        end
      end          
      @world[continent.attributes["name"]] = temp_continent.sort! { |a,b| a <=> b }
    end
  end
  
  def very_pretty_print(continent, countries)
    print "#{continent.upcase}(#{countries.count.to_s}):"
    last_country = countries.pop
    countries.collect! { |c| " #{c}," }
    puts "#{countries.to_s} #{last_country}"
  end
    
end

factbook = Factbook.new("cia-1996.xml")
factbook.find_country_with_highest_population
factbook.find_top_5_countries_by_inflation_rate
factbook.list_continents
factbook.list_countries_by_continent