Binary Tree Implementation and Traversal [Pre-Order, In-Order, Post-Order]

#include<stdio.h>

#include<conio.h>

#include<stdlib.h>

struct node{

int data;

struct node *left,*right;

};

struct node* create(){

int x;

struct node *newnode;

newnode=(struct node*)malloc(sizeof(struct node));

printf("Enter data (-1 for no node): ");

scanf("%d",&x);

if(x==-1)

return 0;

newnode->data=x;

printf("Enter left child of %d: ",x);

newnode->left=create();

printf("Enter right child of %d: ",x);

newnode->right=create();

return newnode;

}

void preorder(struct node *root){

if(root==0)

return;

printf("%d ",root->data);

preorder(root->left);

preorder(root->right);

}

void inorder(struct node *root){

if(root==0)

return;

inorder(root->left);

printf("%d ",root->data);

inorder(root->right);

}

void postorder(struct node *root){

if(root==0)

return;

postorder(root->left);

postorder(root->right);

printf("%d ",root->data);

}

void main(){

struct node *root;

root=0;

root=create();

printf("\nPre-Order is: ");

preorder(root);

printf("\nIn-Order is: ");

inorder(root);

printf("\nPost-Order is: ");

postorder(root);

getch();

}