From: salai <sayakyi@...>
Date: 2009-10-26T21:59:37+09:00
Subject: Hash Reverse ?

I am preparing for my orals exam in Ruby (my last chance.. , If I fail
the test, no more possible to study Computer Science related :-) )

http://codepad.org/foNb9Pd3

class Hash
	def hash_revert
		hash_new = Hash.new
		self.each {|key,value|
			if not hash_new.has_key?(key) then hash_new[value] = key end
		}
		return hash_new
	end
end

h = {2=>"a", 1=> "b", 3 =>"a", 4=> "a", 5 => "b", 6=>"c"}
p h.hash_revert #--> {"a"=>4, "b"=>1, "c"=>6}

or Should I get this ??
# => {"a"=>2, "b"=>1, "c"=>6}

Because HASH is working like "Set" ??

many thanks in advance,
salai.