change shared_ptr to unique_ptr

TinySTL/Detail/TireTree.cpp

@@ -24,16 +24,19 @@ namespace TinySTL{
 		else
 			return _is_existed(word, res->second);
 	}
-	bool trie_tree::_is_existed(const string& word, std::shared_ptr<trie_node> sp)const{
+	bool trie_tree::_is_existed(const string& word, const node_ptr& up)const{
 		if (word.size() == 1)
-			return sp->is_a_word;
+			return up->is_a_word;
 		char ch = word[1];
-		auto res = sp->map_childs.find(ch);
-		if (res == sp->map_childs.end())//not found
+		auto res = up->map_childs.find(ch);
+		if (res == up->map_childs.end())//not found
 			return false;
 		else
 			return _is_existed(word.substr(1), res->second);
 	}
+	trie_tree::node_ptr trie_tree::make_node(char ch, bool is_a_word){
+		return std::make_unique<trie_node>(ch, is_a_word);
+	}
 	bool trie_tree::insert(const string& word){
 		if (is_existed(word))
 			return true;
@@ -45,29 +48,27 @@ namespace TinySTL{
 		if (res != root->map_childs.end()){
 			return _insert(word.substr(1), res->second);
 		}else{
-			auto new_sp = std::make_shared<trie_node>();
-			new_sp->data = ch;
-			new_sp->is_a_word = (word.size() == 1 ? true : false);
-			root->map_childs[ch] = new_sp;
-			return _insert(word.substr(1), new_sp);
+			auto is_a_word = (word.size() == 1 ? true : false);
+			auto node = make_node(ch, is_a_word);
+			root->map_childs[ch] = std::move(node);
+			return _insert(word.substr(1), root->map_childs[ch]);
 		}
 	}
-	bool trie_tree::_insert(const string& word, std::shared_ptr<trie_node> sp){
+	bool trie_tree::_insert(const string& word, const node_ptr& up){
 		if (word.empty()){
 			++size_;
-			sp->is_a_word = true;
+			up->is_a_word = true;
 			return true;
 		}
 		char ch = word[0];
-		auto res = sp->map_childs.find(ch);
-		if (res != sp->map_childs.end()){
+		auto res = up->map_childs.find(ch);
+		if (res != up->map_childs.end()){
 			return _insert(word.substr(1), res->second);
 		}else{
-			auto new_sp = std::make_shared<trie_node>();
-			new_sp->data = ch;
-			new_sp->is_a_word = (word.size() == 1 ? true : false);
-			sp->map_childs[ch] = new_sp;
-			return _insert(word.substr(1), new_sp);
+			auto is_a_word = (word.size() == 1 ? true : false);
+			auto node = make_node(ch, is_a_word);
+			up->map_childs[ch] = std::move(node);
+			return _insert(word.substr(1), up->map_childs[ch]);
 		}
 	}
 	void trie_tree::print_tree(std::ostream& os)const{
@@ -77,11 +78,11 @@ namespace TinySTL{
 		for (auto cit = root->map_childs.cbegin(); cit != root->map_childs.cend(); ++cit)
 			_print_tree(os, cit->second, string());
 	}
-	void trie_tree::_print_tree(std::ostream& os, std::shared_ptr<trie_node> sp, string word)const{
-		word += sp->data;
-		if (sp->is_a_word)
+	void trie_tree::_print_tree(std::ostream& os, const node_ptr& up, string word)const{
+		word += up->data;
+		if (up->is_a_word)
 			os << word << std::endl;
-		for (auto cit = sp->map_childs.cbegin(); cit != sp->map_childs.cend(); ++cit){
+		for (auto cit = up->map_childs.cbegin(); cit != up->map_childs.cend(); ++cit){
 			_print_tree(os, cit->second, word);
 		}
 	}
@@ -96,27 +97,27 @@ namespace TinySTL{
 			_get_word_by_prefix(prefix, res->second, prefix, words);
 		return words;
 	}
-	void trie_tree::_get_word_by_prefix(const string& prefix, std::shared_ptr<trie_node> sp,
+	void trie_tree::_get_word_by_prefix(const string& prefix, const node_ptr& up,
 		const string& real_prefix, vector<string>& words)const{
 		if (prefix.size() == 1){
-			if (sp->is_a_word)
+			if (up->is_a_word)
 				words.push_back(real_prefix);
-			for (auto cit = sp->map_childs.cbegin(); cit != sp->map_childs.cend(); ++cit){
+			for (auto cit = up->map_childs.cbegin(); cit != up->map_childs.cend(); ++cit){
 				__get_word_by_prefix(cit->second, string(), real_prefix, words);
 			}
 		}else{
 			char ch = prefix[1];
-			auto res = sp->map_childs.find(ch);
-			if (res != sp->map_childs.end()){
+			auto res = up->map_childs.find(ch);
+			if (res != up->map_childs.end()){
 				_get_word_by_prefix(prefix.substr(1), res->second, real_prefix, words);
 			}
 		}
 	}
-	void trie_tree::__get_word_by_prefix(std::shared_ptr<trie_node> sp, string& word, const string& prefix, vector<string>& words)const{
-		word += sp->data;
-		if (sp->is_a_word)
+	void trie_tree::__get_word_by_prefix(const node_ptr& up, string& word, const string& prefix, vector<string>& words)const{
+		word += up->data;
+		if (up->is_a_word)
 			words.push_back(prefix + word);
-		for (auto cit = sp->map_childs.cbegin(); cit != sp->map_childs.cend(); ++cit){
+		for (auto cit = up->map_childs.cbegin(); cit != up->map_childs.cend(); ++cit){
 			__get_word_by_prefix(cit->second, string(word), prefix, words);
 		}
 	}

TinySTL/TrieTree.h

@@ -15,9 +15,11 @@ namespace TinySTL{
 		struct trie_node{
 			char data;
 			bool is_a_word;
-			std::map<char, std::shared_ptr<trie_node>> map_childs;
+			std::map<char, std::unique_ptr<trie_node>> map_childs;
 			trie_node() :data('\0'), is_a_word(false){}
+			trie_node(char ch, bool is) :data(ch), is_a_word(is){}
 		};
+		typedef std::unique_ptr<trie_node> node_ptr;
 	public:
 		typedef string value_type;
 		typedef size_t size_type;
@@ -38,12 +40,13 @@ namespace TinySTL{
 		bool insert(const string& word);
 		bool is_existed(const string& word)const;
 	private:
+		node_ptr make_node(char ch, bool is_a_word);
 		inline trie_node* get_root()const{ return data; }
-		void _get_word_by_prefix(const string& prefix, std::shared_ptr<trie_node> sp, const string& real_prefix, vector<string>& words)const;
-		void __get_word_by_prefix(std::shared_ptr<trie_node> sp, string& word, const string& prefix, vector<string>& words)const;
-		void _print_tree(std::ostream& os, std::shared_ptr<trie_node> sp, string word)const;
-		bool _insert(const string& word, std::shared_ptr<trie_node> sp);
-		bool _is_existed(const string& word, std::shared_ptr<trie_node> sp)const;
+		void _get_word_by_prefix(const string& prefix, const node_ptr& up, const string& real_prefix, vector<string>& words)const;
+		void __get_word_by_prefix(const node_ptr& up, string& word, const string& prefix, vector<string>& words)const;
+		void _print_tree(std::ostream& os, const node_ptr& up, string word)const;
+		bool _insert(const string& word, const node_ptr& up);
+		bool _is_existed(const string& word, const node_ptr& up)const;
 	};// end of trie_tree
 }