BinaryTreeTraversal.cpp

// C++ program for different tree traversals
#include <bits/stdc++.h>
using namespace std;

/* A binary tree node has data, pointer to left child
and a pointer to right child */
struct Node {
	int data;
	struct Node *left, *right;
};

// Utility function to create a new tree node
Node* newNode(int data)
{
	Node* temp = new Node;
	temp->data = data;
	temp->left = temp->right = NULL;
	return temp;
}

/* Given a binary tree, print its nodes in inorder*/
void printInorder(struct Node* node)
{
	if (node == NULL)
		return;

	/* first recur on left child */
	printInorder(node->left);

	/* then print the data of node */
	cout << node->data << " ";

	/* now recur on right child */
	printInorder(node->right);
}

/* Given a binary tree, print its nodes in preorder*/
void printPreorder(struct Node* node)
{
    if (node == NULL)
        return;
 
    /* first print data of node */
    cout << node->data << " ";
 
    /* then recur on left subtree */
    printPreorder(node->left);
 
    /* now recur on right subtree */
    printPreorder(node->right);
}

/* Given a binary tree, print its nodes according to the
"bottom-up" postorder traversal. */
void printPostorder(struct Node* node)
{
    if (node == NULL)
        return;
 
    // first recur on left subtree
    printPostorder(node->left);
 
    // then recur on right subtree
    printPostorder(node->right);
 
    // now deal with the node
    cout << node->data << " ";
}

int main()
{
    //Initialization of tree
	struct Node* root = newNode(1);
	root->left = newNode(2);
	root->right = newNode(3);
	root->left->left = newNode(4);
	root->left->right = newNode(5);

	// Function call
	cout << "\nInorder traversal of binary tree is \n";
	printInorder(root);
  
  cout << "\nPreOrder traversal of binary tree is \n";
	printPreorder(root);
  
  cout << "\nPostOrder traversal of binary tree is \n";
	printPostorder(root);


	return 0;
}