4_BST.cpp

#include<iostream>
using namespace std;
struct node
{
    int data;
    node *L;
    node *R;
};
node *root,*temp;
int count,key;

class bst
{
    public:
    void create();
    void insert(node*,node*);
    void disin(node*);
    void dispre(node*);
    void dispost(node*);
    void search(node*,int);
    int height(node*);
    void mirror(node*);
    void min(node*);
    bst()
    {
      root=NULL;
      count=0;
    }
};

void bst::create()
{
    char ans;
    do
    {
        temp=new node;
        cout<<"Enter the data : "; 
        cin>>temp->data;
        temp->L=NULL;
        temp->R=NULL;
        if(root==NULL)
        {
            root=temp;
        }
        else
            insert(root,temp);
        cout<<"Do you want to insert more value : "<<endl; cin>>ans;
        count++;
        cout<<endl;
    }while(ans=='y');
    cout<<"The Total no.of nodes are:"<<count;
} 
void bst::insert(node *root,node* temp) 
{ 
    if(temp->data>root->data)
    {
        if(root->R==NULL)
        {
            root->R=temp;
        }
        else
            insert(root->R,temp);
    }
    else
    {
        if(root->L==NULL)
        {
            root->L=temp;
        }
        else
            insert(root->L,temp);
    }
}

void bst::disin(node *root)
{
    if(root!=NULL)
    {
        disin(root->L);
        cout<<root->data<<"\t"; 
        disin(root->R);
        count++;
    }
}

void bst::dispre(node *root)
{
    if(root!=NULL)
    {
        cout<<root->data<<"\t"; 
        dispre(root->L);
        dispre(root->R);
    }
}

void bst::dispost(node *root)
{
    if(root!=NULL)
    {
        dispost(root->L);
        dispost(root->R);
        cout<<root->data<<"\t";
    }
}

void bst::search(node * root,int key)
{
    int flag=0;
    cout<<"\nEnter your key : "<<endl; 
    cin>>key;
    temp=root;
    while(temp!=NULL)
    {
        if(key==temp->data)
        {
            cout<<"           KEY FOUND           \n"; 
            flag=1; 
            break;  
        } 
        node *parent=temp; 
        if(key>parent->data)
        {
            temp=temp->R;
        }
        else
        {
            temp=temp->L;
        }
    }
    if(flag==0)
    {
        cout<<"            KEY NOT FOUND              "<<endl; 
    
    } 
} 
int bst::height(node *root) 
{ 
    int hl,hr; 
    if(root==NULL)
    { 
        return 0; 
        
    } 
    else if(root->L==NULL && root->R==NULL)
    {
        return 1;
    }
    cout<<endl; 
    hr=1+height(root->R);
    hl=1+height(root->L);
    if(hr>hl)
    {
        return(hr);
    }
    else
    {
        return(hl);
    }   
}

void bst::min(node *root)
{
    temp=root;
    cout<<endl; 
    while(temp->L!=NULL)
    {
        temp=temp->L;
    }
    cout<<temp->data;
}

void bst::mirror(node *root)
{
    temp=root;
    if(root!=NULL)
    {
        mirror(root->L);
        mirror(root->R);
        temp=root->L;
        root->L=root->R;
        root->R=temp;
    }
}

int main()
{
    bst t;
    int ch;
    char ans;
    do
    {
        cout<<"\n1) Insert new node 2)number of nodes in longest path 3) minimum 4) mirror 5) search 6) inorder 7) preorder 8) postorder"<<endl; cin>>ch;
        switch(ch)
        {
            case 1:
                t.create();
                break;
            case 2:
                cout<<"\n Number of nodes in longest path:"<<t.height(root);
                break;
            case 3:
                cout<<"\nThe min element is:";
                t.min(root);
                break;
            case 4:
                t.mirror(root);
                cout<<"\nThe mirror of tree is: ";
                t.disin(root);
                break;
            case 5:
                t.search(root,key);
                break;
            case 6:
                cout<<"\n***************INORDER**************"<<endl;
                t.disin(root);
                break;
            case 7:
                cout<<"\n***************PREORDER**************"<<endl;
                t.dispre(root);
                break;
            case 8:
                cout<<"\n*******************POSTORDER**************"<<endl;
                t.dispost(root);
            break;
        }
        cout<<"\nDo you want to continue : "; cin>>ans;
    }while(ans=='y');
    return 0;
}