BInary_Tree_Introduction

//The following code illustrates the construction of a simple binary tree


#include<stdio.h>
#include<stdlib.h>

// a structure indicating the basic structure of every node of the tree.
struct node 
{
	int data;
	struct node *left;
	struct node *right;
};

//newNode() method allocates a new node with the given data and NULL left and right pointers.
struct node* newNode(int data)
{
// Allocating memory to the new node 
struct node* node = (struct node*)malloc(sizeof(struct node));

// Assign data to this node
node->data = data;
//printing the data to ensure the proper implementation i.e. just for verifying purposes.
printf("\nnew node created with data %d",data);

// Initialize left and right children of node as NULL
node->left = NULL;
node->right = NULL;
return(node);
}

//driver program
int main()
{

struct node *temp; //a temp node for traversing along the tree

// Now create root node with data 1
struct node *root = newNode(1); 

/* following is the tree after above statement 

		 1
		/ \
	      NULL NULL 
*/

//creating new nodes to left and right of root 
root->left	 = newNode(2);
root->right	 = newNode(3);

/* 2 and 3 become left and right children of 1
		  1
		/   \
		2    3
	       / \  / \
	      N  N  N N   // here N stands for NULL 
*/

//Make temp point to the left child of root
temp = root->left;

//creating a new node as left child of temp i.e. left of left of root
temp->left = newNode(4);

/* 4 becomes left child of 2
		1
	    /	    \
	   2	     3
	  / \	    / \
         4   N     N   N
	/ \
       N   N
*/

return 0;
}


//Hope this makes clear on how to create a binary tree :)