Preorder Inorder and postorder traversal of binary search tree in C.

 program:-

#include<stdio.h>

#include<stdlib.h>

struct binary_s_tree

{

int data;

struct binary_s_tree *left;

struct binary_s_tree *right;

};

struct binary_s_tree *root=NULL;

// function for create createnode

struct binary_s_tree *createnode()

{

struct binary_s_tree *n;

n=(struct binary_s_tree*)malloc(sizeof(struct binary_s_tree));

return n;

}

// function insert element into tree

void insert()

{

struct binary_s_tree *temp,*n;

n=createnode();

printf("Enter value\n");

scanf("%d",&n->data);

n->left=NULL;

n->right=NULL;

if(root==NULL)

root=n;

else

{

temp=root;

while(temp!=NULL)

{

if(temp->data>n->data)

{

if(temp->left==NULL)

{

temp->left=n;

temp=temp->left;

}

temp=temp->left;

}

else

{

if(temp->right==NULL)

{

temp->right=n;

temp=temp->right;

}

temp=temp->right;

}

}

}

}

// function for preorder traversal

void preorder_traversal(struct binary_s_tree *temp)

{

if(temp)

{

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

preorder_traversal(temp->left);

preorder_traversal(temp->right);

}

}

// function for post order traversal

void postorder_traversal(struct binary_s_tree *temp)

{

if(temp)

{

postorder_traversal(temp->left);

postorder_traversal(temp->right);

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

}

}

// function for inorder traversal

void inorder_traversal(struct binary_s_tree *temp)

{

if(temp)

{

inorder_traversal(temp->left);

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

inorder_traversal(temp->right);

}

}

int main()

{

int ch;

printf("1. insert element into tree\n");

printf("2. preorder traversal\n");

printf("3. postorder traversal\n");

printf("4. inorder traversal\n");

printf("5. exit\n");

while(1)

{

printf("\nEnter your choice\n");

scanf("%d",&ch);

switch(ch)

{

case 1: insert();

break;

case 2: preorder_traversal(root);

break;

case 3: postorder_traversal(root);

break;

case 4: inorder_traversal(root);

break;

case 5: exit(0);

default: printf("Wrong key\n");

}

}

return 0;

}