Дерево АВЛ: реализовать в данной программе ООП-подход

#include "stdafx.h"
#include <iostream>
#include <cctype>
#include <stdlib.h>
#include <conio.h>
 
using namespace std;
 
struct node
{
 int element;
 node *left;
 node *right;
 int height;
};
typedef struct node *nodeptr;
class bstree
{
 public:
  void insert(int,nodeptr &);
  void del(int, nodeptr &);
  int deletemin(nodeptr &);
  void find(int,nodeptr &);
  nodeptr findmin(nodeptr);
  nodeptr findmax(nodeptr);
  void makeempty(nodeptr &);
  void copy(nodeptr &,nodeptr &);
  nodeptr nodecopy(nodeptr &);
  void preorder(nodeptr);
  void inorder(nodeptr);
  void postorder(nodeptr);
  int bsheight(nodeptr);
  nodeptr srl(nodeptr &);
  nodeptr drl(nodeptr &);
  nodeptr srr(nodeptr &);
  nodeptr drr(nodeptr &);
  int max(int,int);
  int nonodes(nodeptr);
};
// Inserting a node
void bstree::insert(int x,nodeptr &p)
{
 if (p == NULL)
 {
  p = new node;
  p->element = x;
  p->left=NULL;
  p->right = NULL;
  p->height=0;
  if (p==NULL)
  {
   cout<<"Out of Space\n"<<endl;
  }
 }
 else
 {
  if (x<p->element)
  {
   insert(x,p->left);
   if ((bsheight(p->left) - bsheight(p->right))==2)
   {
    if (x < p->left->element)
    {
     p=srl(p);
    }
    else
    {
     p = drl(p);
    }
   }
  }
  else if (x>p->element)
  {
   insert(x,p->right);
   if ((bsheight(p->right) - bsheight(p->left))==2)
   {
    if (x > p->right->element)
    {
     p=srr(p);
    }
    else
    {
     p = drr(p);
    }
   }
  }
  else
  {
   cout<<"Element Exists\n"<<endl;
  }
}
int m,n,d;
m=bsheight(p->left);
n=bsheight(p->right);
d=max(m,n);
p->height = d + 1;
}
// Finding the Smallest
nodeptr bstree::findmin(nodeptr p)
{
 if (p==NULL)
 {
  cout<<"The tree is empty\n"<<endl;
  return p;
 }
 else
 {
  while(p->left !=NULL)
  {
   p=p->left;
   //return p;
  }
  return p;
 }
}
// Finding the Largest node
nodeptr bstree::findmax(nodeptr p)
{
 if (p==NULL)
 {
  cout<<"The tree is empty\n"<<endl;
  return p;
 }
 else
 {
  while(p->right !=NULL)
  {
   p=p->right;
   //return p;
  }
  return p;
 }
}
// Finding an element
void bstree::find(int x,nodeptr &p)
{
 if (p==NULL)
 {
  cout<<"Sorry! element not found\n"<<endl;
 }
 else
 {
  if (x < p->element)
  {
   find(x,p->left);
  }
  else
  {
   if (x>p->element)
   {
    find(x,p->right);
   }
   else
   {
    cout<<"Element found!\n"<<endl;
   }
  }
 }
}
// Copy a tree
void bstree::copy(nodeptr &p,nodeptr &p1)
{
 makeempty(p1);
 p1 = nodecopy(p);
}
// Make a tree empty
void bstree::makeempty(nodeptr &p)
{
 nodeptr d;
 if (p != NULL)
 {
  makeempty(p->left);
  makeempty(p->right);
  d=p;
  free(d);
  p=NULL;
 }
}
// Copy the nodes
nodeptr bstree::nodecopy(nodeptr &p)
{
 nodeptr temp;
 if (p==NULL)
 {
  return p;
 }
 else
 {
  temp = new node;
  temp->element = p->element;
  temp->left = nodecopy(p->left);
  temp->right = nodecopy(p->right);
  return temp;
 }
}
 
// Deleting a node
void bstree::del(int x,nodeptr &p)
{
 nodeptr d;
 if (p==NULL)
 {
  cout<<"Sorry! element not found\n"<<endl;
 }
 else if ( x < p->element)
 {
  del(x,p->left);
 }
 else if (x > p->element)
 {
  del(x,p->right);
 }
 else if ((p->left == NULL) && (p->right == NULL))
 {
  d=p;
  free(d);
  p=NULL;
  cout<<"Element deleted successfully\n"<<endl;
 }
 else if (p->left == NULL)
 {
  d=p;
  free(d);
  p=p->right;
  cout<<"Element deleted successfully\n"<<endl;
 }
 else if (p->right == NULL)
 {
  d=p;
  p=p->left;
  free(d);
  cout<<"Element deleted successfully\n"<<endl;
 }
 else
 {
  p->element = deletemin(p->right);
 }
}
 
int bstree::deletemin(nodeptr &p)
{
 int c;
 cout<<"inside deltemin\n"<<endl;
 if (p->left == NULL)
 {
  c=p->element;
  p=p->right;
  return c;
 }
 else
 {
  c=deletemin(p->left);
  return c;
 }
}
void bstree::preorder(nodeptr p)
{
 if (p!=NULL)
 {
  cout<<p->element<<"\t";
  preorder(p->left);
  preorder(p->right);
 }
}
 
// Inorder Printing
void bstree::inorder(nodeptr p)
{
 if (p!=NULL)
 {
  inorder(p->left);
  cout<<p->element<<"\t";
  inorder(p->right);
 }
}
 
// PostOrder Printing
void bstree::postorder(nodeptr p)
{
 if (p!=NULL)
 {
  postorder(p->left);
  postorder(p->right);
  cout<<p->element<<"\t";
 }
}
 
int bstree::max(int value1, int value2)
{
 return ((value1 > value2) ? value1 : value2);
}
int bstree::bsheight(nodeptr p)
{
 int t;
 if (p == NULL)
 {
  return -1;
 }
 else
 {
  t = p->height;
  return t;
 }
}
 
nodeptr bstree:: srl(nodeptr &p1)
{
 nodeptr p2;
 p2 = p1->left;
 p1->left = p2->right;
 p2->right = p1;
 p1->height = max(bsheight(p1->left),bsheight(p1->right)) + 1;
 p2->height = max(bsheight(p2->left),p1->height) + 1;
 return p2;
}
nodeptr bstree:: srr(nodeptr &p1)
{
 nodeptr p2;
 p2 = p1->right;
 p1->right = p2->left;
 p2->left = p1;
 p1->height = max(bsheight(p1->left),bsheight(p1->right)) + 1;
 p2->height = max(p1->height,bsheight(p2->right)) + 1;
 return p2;
}
nodeptr bstree:: drl(nodeptr &p1)
{
 p1->left=srr(p1->left);
 return srl(p1);
}
nodeptr bstree::drr(nodeptr &p1)
{
 p1->right = srl(p1->right);
 return srr(p1);
}
 
int bstree::nonodes(nodeptr p)
{
 int count=0;
 if (p!=NULL)
 {
  nonodes(p->left);
  nonodes(p->right);
  count++;
 }
 return count;
}
 
int main()
{
 //clrscr();
 nodeptr root,root1,min,max;//,flag;
 int a,choice,findele,delele;
 char ch='y';
 bstree bst;
 
 //system("clear");
 root = NULL;
 root1=NULL;
 cout<<"\n\t\t\t\tWELCOME TO AVL TREE"<<endl;
 cout<<"\t\t\t\t:::::::::::::::::::\n"<<endl;
 
 do
 {
  cout<<"\t\t::::::::::::::::::::::::::::::::::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 1 to insert a new node::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 2 to find the minimum value:::::::::::"<<endl;
  cout<<"\t\t::::Enter 3 to find the max value:::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 4 to search a value:::::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 5 to delete a value:::::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 6 to display Preorder:::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 7 to display Inorder::::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 8 to display Postorder::::::::::::::::"<<endl;
  cout<<"\t\t::::Enter 9 to display the height of the tree:::"<<endl;
  cout<<"\t\t::::Enter 0 to exit:::::::::::::::::::::::::::::"<<endl;
  cout<<"\t\t::::::::::::::::::::::::::::::::::::::::::::::::\n"<<endl;
  
  cout<<"\nEnter the choice: ";
  cin>>choice;
  
  switch(choice)
  {
   case 1:
    cout<<"\n\t\tADDING NEW NODE"<<endl;
    cout<<"\t\t:::::::::::::\n"<<endl;
    cout<<"Enter a new value: ";
    cin>>a;
    bst.insert(a,root);
    cout<<"\nThe new value have been added to your tree successfully\n"<<endl;
    break;
   case 2:
    if (root !=NULL)
    {
     min=bst.findmin(root);
     cout<<"\nThe minimum element in the tree is: "<<min->element<<endl;
    }
    break;
   case 3:
    if (root !=NULL)
    {
     max=bst.findmax(root);
     cout<<"\nThe maximum element in the tree is: "<<max->element<<endl;
    }
    break;
   case 4:
    cout<<"\nEnter node to search: ";
    cin>>findele;
    if (root != NULL)
    {
     bst.find(findele,root);
    }
    break;
   case 5:
    cout<<"\nEnter node to delete: ";
    cin>>delele;
    bst.del(delele,root);
    bst.inorder(root);
    cout<<endl;
    break;
   case 6:
    cout<<"\n\t\tPRE-ORDER TRAVERSAL"<<endl;
    bst.preorder(root);
    cout<<endl;
    break;
   case 7:
    cout<<"\n\t\tIN-ORDER TRAVERSAL"<<endl;
    bst.inorder(root);
    cout<<endl;
    break;
   case 8:
    cout<<"\n\t\tPOST ORDER TRAVERSAL"<<endl;
    bst.postorder(root);
    cout<<endl;
    break;
   case 9:
    cout<<"\n\t\tHEIGHT\n"<<endl;
    cout<<"The height of the tree is: "<<bst.bsheight(root)<<endl;
      
    break;
   case 0:
    cout<<"\n\tThank your for using AVL tree program\n"<<endl;
    break;
   default:
    cout<<"Sorry! wrong input\n"<<endl;
    break;
  }
  system("pause");
  system("cls");
 }while(choice != 0);
 return 0;
}