Trie，又称单词查找树、前缀树，是一种哈希树的变种。应用于字符串的统计与排序，经常被搜索引擎系统用于文本词频统计-Trie, also known as the word search tree, the prefix tree, is a variant of the hash tree. Applied statistics and sorting of strings, often by the search engine system for text word frequency statistics