İkili arama ağacı postorder ve preorder dolaşımları yanlış

Ben inorder ön siparişe, postorder ve benim ikili arama ağacı baskı gereken yere bu ödev üzerinde çalışıyorum. Ancak, sadece benim inorder yöntemi çalışıyor gibi görünüyor. İşimi kontrol etmek şu test vakası kullandık.

http://www.theteacher99.btinternet.co.uk/theteacher/newalevel/cp4_5_4.htm

Aşağıda benim kod bakmak ve yanlış yapıyorum görebiliyor. Herhangi bir yardım / yönlendirme takdir. Sen sadece bana ben yanlış yapıyorum bildirin Benim için bunu çözmek gerekmez. Teşekkürler.

#include <iostream>
#include <fstream>
#include <cstddef>
#include <string>
#include <sstream>
#include <string>

using namespace std;

struct TreeNode
{
    string item;
    TreeNode *left;
    TreeNode *right;
};

class BinarySortTree
{
public:
    BinarySortTree();
    void readFile(string fileName);
    void insert(string key);
    void preorder();
    void postorder();
    void inorder();
    void test();

private:
    TreeNode *root;
    void insert(string key, TreeNode *node);
    void preorderTraverse(TreeNode *node);
    void postorderTraverse(TreeNode *node);
    void inorderTraverse(TreeNode *node);
};


//default constructor, create new binary tree
BinarySortTree::BinarySortTree()
{
    root = NULL;
}

//reads the file and puts items in the tree
void BinarySortTree::readFile(string fileName)
{
    ifstream inputStream(fileName.c_str());

    if(inputStream.is_open())
    {
        string line;

        while( getline(inputStream, line) )
        {
            insert(line);
        }
    }
}

void BinarySortTree::insert(string key)
{
    if(root != NULL)
    {
        insert(key, root);
    }
    else
    {
        root = new TreeNode;
        root->item = key;
        root->left = NULL;
        root->right = NULL;
    }
}

void BinarySortTree::insert(string key, TreeNode *node)
{
    bool done = false;

    while(!done)
    {
        if(key.compare(node->item) < 0)
        {
            if(node->left != NULL)
            {
                node = node->left;
            }
            else
            {
                node->left = new TreeNode;
                node->left->item = key;
                node->left->left = NULL;
                node->left->right = NULL;
                done = true;
            }
        }
        else if(key.compare(node->item) > 0)
        {
            if(node->right != NULL)
            {
                node = node->right;
            }
            else
            {
                node->right = new TreeNode;
                node->right->item = key;
                node->right->left = NULL;
                node->right->right = NULL;
                done = true;
            }
        }
        else if(key.compare(node->item) == 0)
        {
            done = true;
        }
    }
}

void BinarySortTree::preorder()
{
    cout << PreOrder Traversal << endl;
    preorderTraverse(root);
    cout << endl;

}

/*
   1. Start at the root node
   2. Traverse the left subtree
   3. Traverse the right subtree
*/
void BinarySortTree::preorderTraverse(TreeNode *node)
{
    if(node != NULL)
    {
        cout << node->item <<  ;
        preorderTraverse(node->left);
        preorderTraverse(node->right);
    }

}

void BinarySortTree::postorder()
{
    cout << PostOrder Traversal << endl;
    postorderTraverse(root);
    cout << endl;
}

/*
   1. Traverse the left subtree
   2. Traverse the right subtree
   3. Visit the root node
*/
void BinarySortTree::postorderTraverse(TreeNode *node)
{
    if(node != NULL)
    {
        postorderTraverse(node->left);
        postorderTraverse(node->right);
        cout << node->item <<  ;
    }
}

void BinarySortTree::inorder()
{
    cout << InOrder Traversal << endl;
    inorderTraverse(root);
    cout << endl;
}

/*
   1. Traverse the left subtree
   2. Visit the root node
   3. Traverse the right subtree
*/
void BinarySortTree::inorderTraverse(TreeNode *node)
{
    if(node!= NULL)
    {
        inorderTraverse(node->left);
        cout << node->item <<  ;
        inorderTraverse(node->right);
    }
}

void BinarySortTree::test()
{
    cout << root->item << endl;
}


int main()
{
    string fileName = a4.txt;
    BinarySortTree bst;
    bst.readFile(fileName);
    bst.test();

    bst.preorder();
    bst.postorder();
    bst.inorder();

    return 0;
}