AddandSearchWordDatastructuredesign【LeetCode】

<pre name="code" class="java">import java.util.LinkedList;
import java.util.Queue;

import leetcode.ImplementTriePrefixTree2.TrieNode;

/* Design a data structure that supports the following two 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") -> false
* search("bad") -> true
* search(".ad") -> true
* search("b..") -> true
* Note:
* You may assume that all words are consist of lowercase letters a-z.
* You should be familiar with how a Trie works. If not, please work on this problem: Implement Trie (Prefix Tree) first.
*/
//Array Implement

public class AddandSearchWordDatastructuredesign {
class TrieNode {
TrieNode[] children;
boolean flag;

public TrieNode() {
this.children = new TrieNode[26];
this.flag = false;
}
}

public TrieNode root = new TrieNode();

// Adds a word into the data structure.
public void addWord(String word) {
if (word == null || word.length() == 0)
return;
TrieNode node = root;
for (int i = 0; i < word.length(); i++) {
if (node.children[word.charAt(i) - 'a'] == null) {
node.children[word.charAt(i) - 'a'] = new TrieNode();
}
node = node.children[word.charAt(i) - 'a'];
}
node.flag = true;
}

// Returns if the word is in the data structure. A word could
// contain the dot character '.' to represent any one letter.
public boolean search(String word) {
Queue<TrieNode> queue = new LinkedList<TrieNode>();
TrieNode node = root;
queue.add(node);
int index = 0;
while (!queue.isEmpty()) {
if (index == word.length())
return true;
TrieNode curr = queue.poll();
if (word.charAt(index) == '.') {
for (int i = 0; i < 26; i++) {
if (curr.children[i] != null)
queue.add(curr.children[i]);
}
} else {
if (curr != null && curr.children[word.charAt(index) - 'a'] == null)
break;
else
queue.add(curr.children[word.charAt(index) - 'a']);
}
index++;

}
return false;
}
public static void main(String[] args){
System.out.println("ti");
Add a=new Add();
a.addWord("tjos");
a.addWord("b");
System.out.println(a.search("b"));
System.out.println(a.search("tjod"));
}
}

// Your WordDictionary object will be instantiated and called as such:
// WordDictionary wordDictionary = new WordDictionary();
// wordDictionary.addWord("word");
// wordDictionary.search("pattern");