Slip 29 - A) Write a ‘C’ program to create a Binary tree, traverse it using recursive operations like inorder, preorder and postorder and display the result of each one separately.

Solution:

#include<stdio.h>

#include<stdlib.h>

struct binary_tree

{

    int info;

    struct binary_tree *left;

    struct binary_tree *right;

};

typedef struct binary_tree NODE;

NODE *node=NULL;

NODE* init_tree(int data)

{

    NODE* root = (NODE*) malloc (sizeof(NODE));

    root->left = root->right = NULL;

    root->info = data;

    return root;

}

 

NODE* create_node(int data)

{

    NODE* node = (NODE*) malloc (sizeof(NODE));

    node->info = data;

    node->left = node->right = NULL;

    return node;

}

void inorder(NODE *node)

{

     if(node != NULL)

     {

          inorder(node->left);

          printf("%d\t", node->info);

          inorder(node->right);

     }

}

void preorder(NODE *node)

{

     if(node != NULL)

     {

          printf("%d\t", node->info);

          preorder(node->left);

          preorder(node->right);  

     }

}

void postorder(NODE *node)

{

     if(node != NULL)

     {

          postorder(node->left);

          postorder(node->right);

          printf("%d\t", node->info);

     }

}

void main()

{

    NODE* root = init_tree(10);

     

    root->left = create_node(20);

    root->right = create_node(30);

 

    root->left->left = create_node(40);

    root->left->right = create_node(50);

 

    root->right->left = create_node(60);

    root->right->right = create_node(70);

 

    printf("----Preorder Traversal:----\n");

    preorder(root);

    printf("\n\n");

 

    printf("----Inorder Traversal:----\n");

    inorder(root);

    printf("\n\n");

 

    printf("----Postorder Traversal:----\n");

    postorder(root);

    printf("\n\n");

}