添加字典树、并查集、Dijkstra算法

trie_tree.cpp

@@ -0,0 +1,49 @@
+class Trie 
+{
+private:
+	vector<Trie*> m_children;
+	bool is_end;
+
+	Trie* searchPrefix(string prefix)
+	{
+		Trie* node = this;
+		for (char ch : prefix) {
+			if (node->m_children[ch - 'a'] == nullptr) {
+				return nullptr;
+			}
+			node = node->m_children[ch - 'a'];
+		}
+		return node;
+	}
+
+public:
+	Trie() :
+        m_children(26),
+        is_end(false)	
+	{
+
+	}
+
+	void insert(string word) 
+	{
+		Trie* node = this;
+		for (char ch : word) {
+			if (node->m_children[ch - 'a'] == nullptr) {
+				node->m_children[ch - 'a'] = new Trie;
+			}
+			node = node->m_children[ch - 'a'];
+		}
+		node->is_end = true;
+	}
+
+	bool search(string word) 
+	{
+		Trie* node = searchPrefix(word);
+		return node != nullptr && node->is_end;
+	}
+
+	bool startsWith(string prefix) 
+	{
+		return searchPrefix(prefix) != nullptr;
+	}
+};