hash1 = { 1 => "one", 2 => "two", 3 => "three" }
hash2 = Hash[ 3 => "three", 4 => "four", 5 => "five" ]
hash3 = Hash[ 6, "six", 7, "seven", 8, "eight" ]

# make a pretty hash function
class Hash
	def format
		data = self.keys.collect do |key| key = "#{key} => #{self[key]}" end
		"{ #{data.join( ', ' )} }"
	end
end

# useful hash functions
hash1.each_pair do |key, value|
	puts "#{key} => #{value}"
end

# print the hash keys
puts "Keys: [ #{hash1.keys.join( ', ' )} ]"

# print the formatted hash
puts hash1.format

# directly accessing a hash
puts hash1[ 2 ]