BinaryTree.cpp

#include <iostream>

using namespace std;

// Create a class for the BinaryTree
class BinaryTree
{
    // Create a struct for the TreeNode
    struct TreeNode
    {
        // Variables for the TreeNode
        int data;
        TreeNode* left;
        TreeNode* right;

        // Constructor for the TreeNode
        TreeNode(int value) : data(value), left(nullptr), right(nullptr) {}
    };

    // Private Variables and Functions
private:
    TreeNode* root;

    //Insert Function
    TreeNode* insert(TreeNode* root, int value)
    {
        if (root == nullptr)
            return new TreeNode(value);

        if (value < root->data)
            root->left = insert(root->left, value);
        else
            root->right = insert(root->right, value);

        return root;
    }

    // Print Inorder Function
    void printInorder(TreeNode* head)
    {
        if (head != nullptr)
        {
            printInorder(head->left);
            cout << head->data << " ";
            printInorder(head->right);
        }
    }

    // Print Preorder Function
    void printPreorder(TreeNode* head)
    {
        if (head != nullptr)
        {
            cout << head->data << " ";
            printPreorder(head->left);
            printPreorder(head->right);
        }
    }

    // Print Postorder Function
    void printPostorder(TreeNode* head)
    {
        if (head != nullptr)
        {
            printPostorder(head->left);
            printPostorder(head->right);
            cout << head->data << " ";
        }
    }

    // Public Functions
public:
    // Constructor
    BinaryTree() : root(nullptr) {}

    // Insert Function
    void insert(int value)
    {
        root = insert(root, value);
    }

    // Print Inorder Function
    void printInorder()
    {
        printInorder(root);
        cout << endl;
    }

    // Print Preorder Function
    void printPreorder()
    {
        printPreorder(root);
        cout << endl;
    }

    // Print Postorder Function
    void printPostorder()
    {
        printPostorder(root);
        cout << endl;
    }
};

int main()
{
    // Create tree
    BinaryTree binaryTree;

    binaryTree.insert(10);
    binaryTree.insert(6);
    binaryTree.insert(15);
    binaryTree.insert(3);
    binaryTree.insert(8);
    binaryTree.insert(20);

    cout << "InOrder: ";
    binaryTree.printInorder();

    cout << "PreOrder: ";
    binaryTree.printPreorder();

    cout << "PostOrder: ";
    binaryTree.printPostorder();

    return 0;
}