Thread: Getting a "Segmentation Fault: 11" implementing a Binary Search Tree

Hello all,

I'm currently trying to implement a Red-Black Tree, but for now I am using the Vanilla BST insertion implementation (baby steps). I am getting a Segmentation Fault inserting the elements. Here is what I have:

node.h:

Code:

#ifndef Header_h
    #define Header_h
    #include <iostream>

    template <class T>
    class RBNode {
      public:
        T data;
        /* - red = 1
            - black = 0 */
        int color;
        /* - index 0 is the left node
           - index 1 is the right node*/
        RBNode *link[2];
    
        RBNode(const T& d = T(), RBNode *l = NULL,
                     RBNode *r = NULL, int c = 1) {
          data = d;
          link[0] = l;
          link[1] = r;
          color = c;
       }
    };

    #endif

tree.h:

Code:

    #ifndef tree_h
    #define tree_h
    #include "node.h"


    template <class T>
    class RBTree {
    private:
      RBNode<T> *root;
      void insert_entry(RBNode<T> *&node, const T& entry);
      void print_entries(RBNode<T> *node);
      void tree_clear(RBNode<T> *&r) {
          if(r != NULL){
              tree_clear(r->link[0]);
              tree_clear(r->link[1]);
              delete r;
              r = NULL;
          }
      }
    public:
      RBTree() {
          root = NULL;
      }
      ~RBTree() {
          tree_clear(root);
        }
      void insert(const T& entry);
      void print();
    };

    template <class T>
    void RBTree<T>::insert_entry(RBNode<T> *&node, const T& entry) {
      if(node == NULL)
          node = new RBNode<T>(entry);
      else {
          int dir = root->data < entry;
          insert_entry(root->link[dir], entry);
      }
    }


    template <class T>
    void RBTree<T>::print_entries(RBNode<T> *node) {
        print_entries(node->link[0]);
        std::cout << node->data << " ";
        print_entries(node->link[1]);
    }


    template <class T>
    void RBTree<T>::insert(const T& entry) {
        insert_entry(root, entry);
    }


    template <class T>
    void RBTree<T>::print() {
       print_entries(root);
       std::cout << "\n";
    }

#endif