完全模板化

homework4/BiTree.h

@@ -17,6 +17,37 @@ public:
     {
     }
 
+    static bool is_empty(BiTree* bt)
+    {
+        if (bt == nullptr)
+        {
+            return true;
+        }
+        return false;
+    }
+
+    static bool is_leaf(BiTree* bt)
+    {
+        if (bt->left == nullptr && bt->right == nullptr)
+        {
+            return true;
+        }
+        return false;
+    }
+
+    static T sum_leaf(BiTree* bt)
+    {
+        if (is_empty(bt))
+        {
+            return 0;
+        }
+        if (is_leaf(bt))
+        {
+            return bt->data;
+        }
+        return sum_leaf(bt->left) + sum_leaf(bt->right);
+    }
+
     static BiTree* createNode(const T& value)
     {
         BiTree* node = new BiTree();
@@ -26,6 +57,25 @@ public:
         return node;
     }
 
+    static void insertNode(BiTree*& bt, T value)
+    {
+        if (bt == nullptr)
+        {
+            bt = createNode(value);
+        }
+        else
+        {
+            if (value < bt->data)
+            {
+                insertNode(bt->left, value);
+            }
+            if (value > bt->data)
+            {
+                insertNode(bt->right, value);
+            }
+        }
+    }
+
     static BiTree* buildFromPreorderString(const std::string& preorder, size_t& index)
     {
         if (index >= preorder.size() || preorder[index] == '#')
@@ -67,7 +117,7 @@ public:
         this->toStringHelper(oss, "", false, false);
         return oss.str();
     }
-    
+
     void destroy()
     {
         if (left)