Add and Search Word

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题目描述：

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.

AC代码如下（时间：85ms

class TrieNode {
public:
	// Initialize your data structure here.
	TrieNode(){
		m_isWord = false;
		for (int i = 0; i < 26; ++i){
			next[i] = NULL;
		}
	}
	void setIsWord(bool isWord){
		m_isWord = isWord;
	}
	bool getIsWord(void){
		return m_isWord;
	}
public:
	bool m_isWord;
	TrieNode* next[26];
};

class WordDictionary {
public:
	WordDictionary(){
		root = new TrieNode();
	}
	// Adds a word into the data structure.
	void addWord(string word) {
		int len = word.length();
		if (len == 0) return;
		TrieNode* p = root;
		for (int i = 0; i < len; ++i){
			if (p->next[word[i] - 'a'] == NULL){
				p->next[word[i] - 'a'] = new TrieNode();
				p = p->next[word[i] - 'a'];
			}
			else{
				p = p->next[word[i] - 'a'];
			}
		}
		p->setIsWord(true);
	}
	bool search(string word){
		return search(word, 0, root);
	}
	// Returns if the word is in the data structure. A word could
	// contain the dot character '.' to represent any one letter.
	bool search(const string& word,int curIndex,TrieNode* curNode) {
		if (curIndex == word.length()) return curNode->getIsWord();
		if (word[curIndex] == '.'){
			bool res = false;
			for (int i = 0; i < 26; ++i){
				if (curNode->next[i] != NULL){
					res = search(word, curIndex + 1, curNode->next[i]);
					if (res) return true;
				}
			}
			return false;
		}
		else{
			if (curNode->next[word[curIndex] - 'a'] != NULL){
				return search(word, curIndex + 1, curNode->next[word[curIndex] - 'a']);
			}
			else{
				return false;
			}
		}
	}
private:
	TrieNode* root;
};

Add and Search Word

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原文地址：http://blog.csdn.net/lyh642784803/article/details/51345992