如果您要处理的是大型数据集,建议您考虑将其实现。我将一小部分Ruby做到了这一点:
require 'rubygems'
require 'redis'
class RedisTrie
TERMINAL = '+'
def initialize(prefix)
@prefix = prefix
@r = Redis.new
end
def add_word(word)
w = word.gsub(/[^a-zA-Z0-9_-]/, '')
key = "#{@prefix}:"
w.each_char do |c|
@r.zset_add key, c.bytes.first, c
key += c
end
@r.zset_add key, 0, TERMINAL
end
def add_words(*words)
words.flatten.compact.each {|word| add_word word}
end
def suggest(text)
@r.zset_range("#{@prefix}:#{text}", 0, -1).map do |c|
(c == TERMINAL) ? text : suggest(text + c)
end.flatten
end
end
rt = RedisTrie.new('trie')
rt.add_words %w( apple automobile carwash oil-change cranky five ruthie axe auto )
p rt.suggest(ARGV.shift.to_s)
例如:
$ ruby RedisTrie.rb
["apple", "auto", "automobile", "axe", "carwash", "cranky", "five", "oil-change", "ruthie"]
$ ruby RedisTrie.rb a
["apple", "auto", "automobile", "axe"]
$ ruby RedisTrie.rb au
["auto", "automobile"]
$ ruby RedisTrie.rb aux
[]
在Wikipedia的Tries条目上阅读有关Tries的更多信息。
您肯定会优化您的建议方法,以不返回所有值,而只返回找到的前X个值。这将使迭代整个数据结构的目的无效。