From: James Edward Gray II <james@...>
Date: 2005-11-14T23:35:20+09:00
Subject: Re: Recursive functions

On Nov 14, 2005, at 8:21 AM, Brian Schr�der wrote:

> Be carefull. Spoiler below

Brian was faster than me.  My own attempt follows, again, a spoiler...

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James Edward Gray II

def combine( triplets, combinations = [""] )
   chrs   = triplets.shift.split("")
   combos = combinations.map { |combo| chrs.map { |chr| combo +  
chr } }.flatten

   combos.delete_if do |start|
     !$dict[start.length + triplets.length].any? { |word| word =~ /^# 
{start}/ }
   end

   if triplets.empty?
     combos
   else
     combine(triplets, combos)
   end
end

warn "Loading dictionary..." if $DEBUG
$dict = Hash.new { |words, len| words[len] = Array.new }
File.foreach("/usr/share/dict/words") do |line|
   word = line.downcase.delete("^a-z")
   $dict[word.length] << word
end
warn "Loaded." if $DEBUG

warn "Building word list:" if $DEBUG
puts
DATA.each_line("") do |line|
   puts combine(line.strip.downcase.split)
   puts
end

__END__
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