ADSL Threaded Binary Tree (TBT)

#include<iostream>
using namespace std;

class node
{
public:
node *left, *right;
int lbit, rbit, data;
};

class tbt
{
public:
node *root,*temp,*dummy;
void createtbt();
void display();
void isttbt(node*,node*);
tbt()
{
dummy=root=temp=NULL;
}
};

void tbt::createtbt()
{
int val;
char op;
do
{
temp=new node;
cout<<"\n Insert new value: ";
cin>>val;
temp->data=val;
temp->left=NULL;
temp->right=NULL;
temp->lbit=0;
temp->rbit=0;
if(root==NULL)
{
dummy=new node;
dummy->data=999;
dummy->left=temp;
dummy->right=dummy;
dummy->lbit=1;
dummy->rbit=0;
root=temp;
root->left=dummy;
root->right=dummy;
}
else
isttbt(root,temp);
cout<<"\n Do you want to continue?(y/n) ";
cin>>op;
}while(op=='y');
}

void tbt::isttbt(node *root,node *temp)
{
if(temp->data>root->data)
{
if(root->lbit==0)
{
root->left=temp;
temp->right=root;
temp->left=root->left;
root->lbit=1;
}
else
isttbt(root->left,temp);
}
else
{
if(root->rbit==0)
{
root->right=temp;
temp->left=root;
temp->right=root->right;
root->rbit=1;
}
else
isttbt(root->right,temp);
}
}

void tbt::display()
{
temp=root;
while(temp->lbit!=0)
{
temp=temp->left;
}
while(temp!=root)
{
cout<<"\t"<<temp->data;
temp=temp->right;
}
//temp=temp->right;
cout<<"\t"<<temp->data;
temp=temp->right;
while(temp->lbit!=0)
{
temp=temp->left;
}
while(temp!=dummy)
{
cout<<"\t"<<temp->data;
temp=temp->right;
}
}

int main()
{
tbt f;
f.createtbt();
f.display();
return 0;
}