g0201_0300.s0211_design_add_and_search_words_data_structure

Class WordDictionary

java.lang.Object

g0201_0300.s0211_design_add_and_search_words_data_structure.WordDictionary

public class WordDictionary
extends Object

211 - Design Add and Search Words Data Structure.

Medium

Design a data structure that supports adding new words and finding if a string matches any previously added string.

Implement the WordDictionary class:

• WordDictionary() Initializes the object.
• void addWord(word) Adds word to the data structure, it can be matched later.
• bool search(word) Returns true if there is any string in the data structure that matches word or false otherwise. word may contain dots '.' where dots can be matched with any letter.

Example:

Input

["WordDictionary","addWord","addWord","addWord","search","search","search","search"] [ [],["bad"],["dad"],["mad"],["pad"],["bad"],[".ad"],["b.."]]

Output

[null,null,null,null,false,true,true,true]

Explanation

WordDictionary wordDictionary = new WordDictionary();
wordDictionary.addWord("bad");
wordDictionary.addWord("dad");
wordDictionary.addWord("mad");
wordDictionary.search("pad"); // return False
wordDictionary.search("bad"); // return True
wordDictionary.search(".ad"); // return True
wordDictionary.search("b.."); // return True 

Constraints:

• 1 <= word.length <= 500
• word in addWord consists lower-case English letters.
• word in search consist of '.' or lower-case English letters.
• At most 50000 calls will be made to addWord and search.

Constructor Summary

Constructors

Constructor and Description
WordDictionary()

Method Summary

Modifier and Type	Method and Description
void	addWord(String word)
boolean	dfs(g0201_0300.s0211_design_add_and_search_words_data_structure.WordDictionary.Node root, String word, int index)
boolean	search(String word)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

WordDictionary

public WordDictionary()

Method Detail

addWord

public void addWord(String word)

search

public boolean search(String word)

dfs

public boolean dfs(g0201_0300.s0211_design_add_and_search_words_data_structure.WordDictionary.Node root,
                   String word,
                   int index)