Trie 字典树 Objective-c 算法实现

下载地址： http://github.com/nathanday/ndtrie

NDTrie was developed for text completion, using the method -[NDTrie everyObjectForKeyWithPrefix:] will return every
string with the given prefix. For example an NDTrie with the strings {cat, catalog, category, cow, dog} for
everyObjectForKeyWithPrefix:@"cat" return the strings {cat, catalog, category}.
The NDTrie project contains two classes NDTrie and a subclass NDMutableTrie, which work the same way Apples mutable and
non-mutable classes work.
Though initially developed to contain strings that act as the key and value using methods like -[NSMutableTrie
addString:], NDTrie can also contain any object with a string key using methods like -[NSMutableTrie
setObject:forKey:].

之所以选择这个开源组件，是我着手开发一个英文字段软件。
词库量较大，有4W条记录，通过sqlite的like查询，效率很低。使用了这个组件之后，效果更差！
最终的解决方法还是在数据库上做文章，首先根据单词顺序进行排序，分别记录不同字母开头单词所在区域，其次创建索引，查询时，根据用户输入的关键字，再给定范围内进行模糊查询。目前速度还算满意。