Binary Tree

/**

 * This is an example for how to use a binary tree.

*/

#include <bits/stdc++.h>

using namespace std;

class TreeNode{

public:

    int data;

    TreeNode * left, * right;

};

class BinaryTree{

public:

    BinaryTree()

    {

    }

    TreeNode * newNode(int val)

    {

        TreeNode * mynode = new TreeNode();

        mynode->data = val;

        mynode->left = nullptr;

        mynode->right = nullptr;

        return mynode;

    }

    TreeNode * insertNode(TreeNode * root, int val)

    {

        if(root == nullptr)

            return newNode(val);

        if (val < root->data)

            root->left = insertNode(root->left, val);

        else

            root->right = insertNode(root->right, val);

        return root;

    }

    void inorder(TreeNode *root)

    {

        if (root != nullptr)

        {

            inorder(root->left);

            cout<<root->data<<",";

            inorder(root->right);

        }

    }

    void preorder(TreeNode *root)

    {

        if (root != nullptr)

        {

            cout<<root->data<<",";

            preorder(root->left);

            preorder(root->right);

        }

    }

    void postorder(TreeNode *root)

    {

        if (root != nullptr)

        {

            postorder(root->left);

            postorder(root->right);

            cout<<root->data<<",";

        }

    }

};

int main()

{

    BinaryTree mytree = BinaryTree();

    TreeNode * root = nullptr;

    root = mytree.insertNode(root,50);

    mytree.insertNode(root,30);

    mytree.insertNode(root,20);

    mytree.insertNode(root,40);

    mytree.insertNode(root,70);

    mytree.insertNode(root,60);

    mytree.insertNode(root,80);

    cout<<"inorder"<<endl;

    mytree.inorder(root);

    cout<<endl;

    cout<<"preorder"<<endl;

    mytree.preorder(root);

    cout<<endl;

    cout<<"postorder"<<endl;

    mytree.postorder(root);

    cout<<endl;

    return 0;

}