kw.rb

require 'json'

kw = %w{
_Bool _Complex _Noreturn _Imaginary
auto asm break case char
continue const comp default do
double else enum extern extended
float for goto if int
inline long pascal
register restrict return
short sizeof static struct switch
segment signed typedef union unsigned
void volatile while
}

@T = [].fill(0,256) {|x| x }.sample(256)
@Used = [].fill(0,256) {|x| false }

def hash(str, target=nil)

	#raise "Target already used: #{target}" if @Used[target]

	h = 0
	used = {}
	used.default = 0
	stack = []

	str.each_byte{|c| 

		h = h ^ c;
		used[h] = used[h] + 1
		stack.push(h)
		h = @T[h]
	}

	puts "#{str}: #{h} : #{target}"
	puts "Used: ",JSON.generate(stack)


	# str = "a" = 97, target = 1
	# h = T[97]
	# hh = [97]
	# update so T[97] = target, T[xxx] = T[97] 

	# best case - h IS the target
	if h == target || target == nil
		stack.each{|x| @Used[x] = true}
		return h
	end

	# can't swap elements if it was previously used.
	last = stack.last
	raise "oops! #{last}" if used[last] > 1
	raise "oops! #{last}" if @Used[last]

	index = @T.find_index(target)
	raise "oops! #{index}" if used[index] > 0
	raise "oops! #{index}" if @Used[index]

	# also try updating @T[stack[-2]] to point to index.


	@T[index], @T[last] = @T[last], @T[index]

	# update the used list
	stack.each{|x| @Used[x] = true}
	return target
end


target = 0
hhh = {}
hhh.default = 0
kw.sort!
kw.each{|str|
	target = target + 1
	h = hash(str)
	hhh[h] = hhh[h] + 1
}

puts JSON.generate(@T)
puts JSON.generate(hhh)
#puts JSON.generate(@Used)
exit

kw.sort!

hash_list = []
kw.each {|str|
	h = hash(str)
	hash_list[h] ||= []
	hash_list[h].push(str)
}

puts JSON.generate(hash_list)

puts hash_list.select {|a| a }.inject{|a, b| a.length > b.length ? a : b }.length

exit

# kw.each {|str|

# 	hash = 0
# 	str.each_byte{|x| hash = hash + x}

# 	printf("%04x %s\n", hash , str)
# }

prev = ""
kw.each {|str|

	first = str[0]
	if first != prev
		puts "			end;" unless prev == ""
		puts "		case '#{first}': begin"
		prev = first
	end

	h = hash(str) & 0x3f
	value = str.downcase.gsub(/^_/, '')
	value += 'sy'
	puts "			if hash = #{h} then if str = '#{str}' then kw := #{value};"

}
puts "			end;" unless prev == ""