Leetcode 208Implement Trie (Prefix Tree)

Implement a trie with insert , search , and startsWith methods.

Note:
You may assume this all inputs is consist of lowercase letters a-z .

Building a dictionary Tree

classTrienode {CharC; HashMap<character, trienode> children=NewHashmap<character, trienode>(); BooleanHasword;  PublicTrienode () {} PublicTrienode (Charc) {         This. c=C; }} Public classtrie{PrivateTrienode Root;  PublicTrie () {root=NewTrienode (); }         Public voidInsert (String word) {Trienode cur=Root; HashMap<character, trienode> curchildren=Root.children; Char[] wordarray=Word.tochararray ();  for(inti=0;i<wordarray.length;i++){            CharWc=Wordarray[i]; if(Curchildren.containskey (WC)) {cur=curchildren.get (WC); }Else{Trienode NewNode=NewTrienode (WC);                Curchildren.put (WC, newNode); Cur=NewNode; } Curchildren=Cur.children; if(i==wordarray.length-1) {Cur.hasword=true; }        }    }         Public BooleanSearch (String word) {if(Searchwordnodepos (word) = =NULL){            return false; }Else if(Searchwordnodepos (Word). Hasword) {return true; }Else return false; }         Public BooleanstartsWith (String prefix) {if(Searchwordnodepos (prefix) = =NULL){            return false; }Else return true; }    PrivateTrienode Searchwordnodepos (String s) {//TODO auto-generated Method StubHashmap<character, trienode> children=Root.children; Trienode cur=NULL; Char[] sarray=S.tochararray ();  for(inti=0;i<sarray.length;i++){            CharC=Sarray[i]; if(Children.containskey (c)) {cur=Children.get (c); Children=Cur.children; }Else{                return NULL; }        }                returncur; }            }//Your Trie object would be instantiated and called as such://Trie Trie = new Trie ();//Trie.insert ("somestring");//trie.search ("key");

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Reference: http://blog.csdn.net/yangliuy/article/details/46287671

Http://www.cnblogs.com/huangxincheng/archive/2012/11/25/2788268.html

Leetcode 208Implement Trie (Prefix Tree)