(Data structure) Implement Trie and Add and Search Word

Implement Trie (Prefix Tree)

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

Note:
Assume that all inputs is consist of lowercase lettersa-z

Solution:

classTrienode {//Initialize your data structure here.    BooleanIsend;    Trienode[] sons; Charvalue;  PublicTrienode () {isend=false; Sons=NewTrienode[26]; }} Public classTrie {PrivateTrienode Root;  PublicTrie () {root=NewTrienode (); }    //inserts a word into the trie.     Public voidInsert (String word) {if(Word = =NULL|| Word.length () = = 0)            return; Trienode P=Root;  for(inti = 0; I < word.length (); i++) {            intpos = Word.charat (i)-' a '; if(P.sons[pos] = =NULL) {P.sons[pos]=NewTrienode (); P.sons[pos].value=Word.charat (i); } P=P.sons[pos]; } p.isend=true; }    //Returns If the word is in the trie.     Public BooleanSearch (String word) {if(Word = =NULL|| Word.length () = = 0)            return false; Trienode P=Root;  for(inti = 0; I < word.length (); i++) {            intpos = Word.charat (i)-' a '; if(P.sons[pos] = =NULL)                return false; P=P.sons[pos]; }        returnP.isend; }    //Returns If there is any word in the trie//That's starts with the given prefix.     Public BooleanstartsWith (String prefix) {if(prefix = =NULL|| Prefix.length () = = 0)            return false; Trienode P=Root;  for(inti = 0; I < prefix.length (); i++) {            intpos = Prefix.charat (i)-' a '; if(P.sons[pos] = =NULL)                return false; P=P.sons[pos]; }        return true; }}//Your Trie object would be instantiated and called as such://Trie Trie = new Trie ();//Trie.insert ("somestring");//trie.search ("key");

Add and Search Word

Design a data structure that supports the following and the operations:

void Addword (Word) bool Search (word)

Search (Word) can search a literal word or a regular expression string containing only letters a-z or . . A . means it can represent any one letter.

For example:

Addword ("Bad") Addword ("Dad") Addword ("Mad") Search ("pad"), Falsesearch ("bad"), Truesearch (". Ad") Truesearch ("B..")-True

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

Solution:

 Public classWorddictionary {PrivateTode Root;  PublicWorddictionary () {root=NewTode (); }        //Adds A word into the data structure.     Public voidAddword (String word) {if(Word = =NULL|| Word.length () = = 0)            return ; Tode P=Root;  for(inti=0; I<word.length (); i++){            intpos = Word.charat (i)-' a '; if(P.sons[pos] = =NULL) {P.sons[pos]=NewTode (); P.sons[pos].value=Word.charat (i); } P=P.sons[pos]; } p.isend=true; }    //Returns If the word is in the data structure. A Word could//contain the dot character '. ' to represent.     Public BooleanSearch (String word) {if(Word = =NULL|| Word.length () = = 0)            return false; Char[] arr =Word.tochararray (); intindex = 0; Tode P=Root; returnGosearch (arr, index, p); }    Private BooleanGosearch (Char[] arr,intindex, Tode p) {        if(Index = =arr.length)returnP.isend; if(Arr[index] = = '. '){             for(Tode n:p.sons) {if(n! =NULL&& Gosearch (arr, index+1, N)) return true; }            return false; }Else{            intpos = Arr[index]-' a '; if(P.sons[pos]! =NULL)                returnGosearch (arr, index+1, P.sons[pos]); Else                return false; }    }    classtode{BooleanIsend;        Tode[] sons; Charvalue;  PublicTode () {isend=false; Sons=NewTode[26]; }    }}//Your Worddictionary object would be instantiated and called as such://worddictionary worddictionary = new Worddictionary ();//Worddictionary.addword ("word");//Worddictionary.search ("pattern");

(Data structure) Implement Trie and Add and Search Word