node depth

tree.cpp

@@ -12,16 +12,22 @@ using Node_ptr = std::unique_ptr<Node<T>>;
 template <typename T>
 struct Node{
     T value;
+    int max_depth;
     Node_ptr<T> small;
     Node_ptr<T> big;
+
+    bool add(T val);
+    bool add_to_child(Node_ptr<T>* child, T val);
+    void update_depth();
     void dump(std::ofstream& ofs) const;
+    Node(T v): value{v}, max_depth{0}, small{nullptr}, big{nullptr}{}
 };
 
 template <typename T>
 class Tree{
     Node_ptr<T> root;
     Node_ptr<T>* find(T val);
-    Node_ptr<T>* find_to_swap(Node_ptr<T>* unwanted);
+    bool try_to_del(Node_ptr<T>* node, T val);
 
 public:
     bool insert(T val);
@@ -39,69 +45,106 @@ Node_ptr<T>* Tree<T>::find(T val){
     return nullptr;
 }
 
-template <typename T>
-Node_ptr<T>* Tree<T>::find_to_swap(Node_ptr<T>* unwanted){
-    if((*unwanted)->small) unwanted = &(*unwanted)->small;
-    else return nullptr;
-    while((*unwanted)->big) unwanted = &(*unwanted)->big;
-    return unwanted;
-}
-
-template <typename T>
-bool Tree<T>::del(T val){
-    Node_ptr<T>* unwanted = find(val);
-    if(!unwanted) return false;
-    Node_ptr<T>* to_swap = find_to_swap(unwanted);
-    if(!to_swap){
-        (*unwanted).reset((*unwanted)->big.release());
-    }
-    else{
-        std::swap((*unwanted)->value, (*to_swap)->value);
-        (*to_swap).reset((*to_swap)->small.release());
-    }
-    return true;
-}
-
 template <typename T>
 bool Tree<T>::insert(T val){
-    std::unique_ptr<Node<T>> node = std::make_unique<Node<T>>();
-    node->value = val;
-    if (!root){
-        root.swap(node);
+    if(!root){
+        root = std::make_unique<Node<T>>(val);
+        return true;
+    }
+    else return root->add(val);
+}
+
+template <typename T>
+bool Node<T>::add(T val){
+    if (val == value)     return false;
+    else if (val < value) return add_to_child(&small, val);
+    else                  return add_to_child(&big, val);
+}
+
+template <typename T>
+bool Node<T>::add_to_child(Node_ptr<T>* child, T val){
+    if(!(*child)){
+        *child = std::make_unique<Node<T>>(val);
+        update_depth();
         return true;
     }
     else{
-        Node<T>* temp = root.get();
-        while(temp){
-            if(val < temp->value){
-                if(temp->small) temp = temp->small.get();
-                else{
-                    temp->small.swap(node);
+        if((*child)->add(val)){
+            update_depth();
             return true;
         }
-            }
-            else if(val > temp->value){
-                if(temp->big) temp = temp->big.get();
-                else{
-                    temp->big.swap(node);
-                    return true;
-                }
-            }
-            else return false;
-        }
         return false;
     }
 }
 
 
+template <typename T>
+bool Tree<T>::del(T val){
+    if(!root) return false;
+    else      return try_to_del(&root, val);
+}
+
+template <typename T>
+bool Tree<T>::try_to_del(Node_ptr<T>* node, T val){
+    if(val == (*node)->value) {
+        Node<T>* temp = (*node).get();
+        std::vector<Node<T>*> path;
+        if((*node)->small) {
+            temp = (*node)->small.get();
+            path.push_back(temp);
+        }
+        else {
+            node->reset((*node)->big.release());
+            return true;
+        }
+        while(temp->big){
+            temp = temp->big.get();
+            path.push_back(temp);
+        }
+        //mam temp na 'to swap' nodu...
+        std::swap((*node)->value, temp->value);
+        //temp->steal_values(std::move(temp->small));
+        for(int i = path.size() -1; i >= 0; i--) path[i]->update_depth();
+        path.clear();
+        return true;
+    }
+    else if(val < (*node)->value){
+        if(!(*node)->small) return false;
+        else {
+            if(try_to_del(&(*node)->small, val)){
+                (*node)->update_depth();
+                return true;
+            }
+            return false;
+        }
+    }
+    else {
+        if(!(*node)->big) return false;
+        else {
+            if(try_to_del(&(*node)->big, val)){
+                (*node)->update_depth();
+                return true;
+            }
+            return false;
+        }
+    }
+}
+
+template <typename T>
+void Node<T>::update_depth(){
+    if(small && big) max_depth = std::max(small->max_depth, big->max_depth) + 1;
+    else if (small) max_depth = small->max_depth + 1;
+    else max_depth = big->max_depth + 1;
+}
+
 template <typename T>
 void Node<T>::dump(std::ofstream& ofs) const {
     if (small) {
-        ofs << value << " -> " << small->value << '\n';
+        ofs << '"' << value << " : " << max_depth << '"' << " -> "  << '"' << small->value << " : " << small->max_depth << '"' << '\n';
         small->dump(ofs);
     }
     if (big) {
-        ofs << value << " -> " << big->value << '\n';
+        ofs << '"' << value << " : " << max_depth << '"' << " -> "  << '"' << big->value << " : " << big->max_depth << '"' << '\n';
         big->dump(ofs);
     }
 }
@@ -120,7 +163,7 @@ void Tree<T>::print() const {
 
 int main(){
     Tree<int> t;
-    std::vector<int> v = {3, 6, 8, -1, 7, 0, 9, 2, -11, 5};
+    std::vector<int> v = {3, 6, 8};
     for(auto i : v){
         if(t.insert(i)) std::cout << "added " << i << "\n";
         else std::cout << "failed at adding " << i << "\n";