39.rb

# create a mapping of state to abbreviation
states = {
  'Oregon' => 'OR',
  'Florida' => 'FL',
  'California' => 'CA',
  'New York' => 'NY',
  'Michigan' => 'MI'
}

# create a basic set of states and some cities in them
cities = {
  'CA' => 'San Francisco',
  'MI' => 'Detroit',
  'FL' => 'Jacksonville'
}

#add cities
cities['IT'] = "Bologna"
cities['DE'] = "Berlin"

puts ' --- '
puts "CA State has: #{cities['CA']}"
puts "DE State has: #{cities['DE']}"

# puts some states
puts '-' * 10
puts "Michigan's abbreviation is: #{states['Michigan']}"
puts "Florida's abbreviation is: #{states['Florida']}"

# do it by using the state then cities dict
puts '-' * 10
puts "Michigan has: #{cities[states['Michigan']]}"
puts "Florida has: #{cities[states['Florida']]}"

#list all
puts "\n ---\n"
states.each do |s_key, s_val|
	puts "key is #{s_key}, value is #{s_val}"
end

# default values using ||= with the nil result
city = cities['TX']
city ||= 'Does Not Exist'
puts "The city for the state 'TX' is: #{city}"