BT_traverse

bt_dfs.c

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

struct node {
    struct node *left;
    int data ;
    struct node *right;
};

struct node *root = NULL;

void insertNode(struct node *q, int data)
{
    if (q == NULL)
    {
        struct node *temp = (struct node *) malloc (sizeof(struct node));
        if (temp == NULL)
        {
            printf("insertNode (%s:%d): malloc failed\n",__FILE__,__LINE__);
            return;
        }
        temp->data = data;
        temp->left = NULL;
        temp->right = NULL;
        root = temp;
       
        printf("insertNode (%s:%d): First Node\n",__FILE__,__LINE__);
        return;
    }
    
    else if (q->data == data )
    {
        printf("insertNode (%s:%d): Duplicate entry\n",__FILE__,__LINE__);
        return;
        
    }
    
    else if (data < q->data && q->left != NULL )
    {
        q = q->left;
        insertNode(q, data);
        
    }
    
    else if (data > q->data && q->right != NULL)
    {
        q = q->right;
        insertNode(q, data);
    }
    
    else if (data < q->data && q->left == NULL )
    {
        struct node *temp = (struct node *)malloc(sizeof(struct node));
        if (temp == NULL)
        {
            printf("insertNode (%s:%d): malloc failed\n",__FILE__,__LINE__);
            return;
        }
        temp->data = data;
        temp->left = NULL;
        temp->right = NULL;
        q->left = temp;
        return;
        
    }

    else if (data > q->data && q->right == NULL )
    {
        struct node *temp = (struct node *)malloc(sizeof(struct node));
        if (temp == NULL)
        {
            printf("insertNode (%s:%d): malloc failed\n",__FILE__,__LINE__);
            return;
        }
        temp->data = data;
        temp->left = NULL;
        temp->right = NULL;
        q->right = temp;
        return;
        
    }

}

void inOrderTraversal(struct node *root)
{
    if(root != NULL)
    {
        inOrderTraversal(root->left);
        printf("%d\n",root->data);
        inOrderTraversal(root->right);
    }    
}


void preOrderTraversal(struct node *root)
{
    if(root != NULL)
    {
        printf("%d\n",root->data);
        preOrderTraversal(root->left);
        preOrderTraversal(root->right);
    }    
}

void postOrderTraversal(struct node *root)
{
    if(root != NULL)
    {
        postOrderTraversal(root->left);
        postOrderTraversal(root->right);
        printf("%d\n",root->data);
    }    
}

void main() {
    int n,x;
    int num_nodes = 7;
    for(x=0;x<num_nodes;x++) {
    
               insertNode(root,x);
    }   
 
    printf("\nInorder Traversal is:\n");
    inOrderTraversal(root);
 
    printf("\nPreorder Traversal is:\n");
    preOrderTraversal(root);
 
    printf("\nPostorder Traversal is:\n");
    postOrderTraversal(root);
}