BT_Creations2.cpp

//method 2 for creating a bst that is filling all the left until -1 is given as input
#include<iostream>
using namespace std;
class Node{
    public:
    int data;
    Node *left, *right;
    Node(int value){
        data=value;
        left=right=NULL;
    };
};

void PreOrder(Node*root){
    if(root==NULL){
        return;
    }
    cout<<root->data;
    PreOrder(root->left);
    PreOrder(root->right);
};

void InOrder(Node*root){
    if(root==NULL){
        return;
    }
    InOrder(root->left);
    cout<<root->data;
    InOrder(root->right);
};

void PostOrder(Node*root){
    if(root==NULL){
        return;
    }
    PostOrder(root->left);
    PostOrder(root->right);
    cout<<root->data;
};

Node*BinaryTree(){
    int x;
    cin>>x;
    if(x==-1){
        return NULL;
    }
    Node*temp=new Node(x);
    cout<<"Enter the left child of "<<x<<" : ";
    temp->left=BinaryTree();
    cout<<"Enter the right child of "<<x<<" : ";
    temp->right=BinaryTree();
    return temp;
}
int main()
{
    //CODE FOR TREE CREATION
    cout<<"Enter the root node:  ";
    Node*root;
    root=BinaryTree();
    //CODE FOR TRAVERSAL
    cout<<"PreOrder:  ";
    PreOrder(root);

    cout<<"\nPostOrder:  ";
    PostOrder(root);

    cout<<"\nInOrder:  ";
    InOrder(root);
    return 0;
}