Binary search tree search.cpp

#include <iostream>
#include<queue>
using namespace std;

class node{
    public:
        int data;
        node*left;
        node*right;

        node(int d){
            data = d;
            left = NULL;
            right = NULL;
        }
};

//Accepts the old root node & data and returns the new root node 
node* insertInBST(node *root,int data){
    //Base Case
    if(root==NULL){
        return new node(data);
    }
    //Rec Case - Insert in the Subtree and Update Pointers
    if(data<=root->data){
        root->left = insertInBST(root->left,data);
    }
    else{
        root->right = insertInBST(root->right,data);
    }
    return root;
}

node* build(){
    //Read a list of numbers till -1 and also these numbers will be inserted into BST
    int d;
    cin>>d;

    node*root = NULL;

    while(d!=-1){
        root = insertInBST(root,d);
        cin>>d;
    }
    return root;
}

//Inorder Print
void inorder(node*root){
    if(root==NULL){
        return;
    }
    inorder(root->left);
    cout<<root->data<<",";
    inorder(root->right);
}
//searching
bool search(node* root,int data){
	if(root==NULL){
		return false;
	}
	if(root->data==data){
		return true;
	}
	//recursively search in left and right subtree
	if(data<=root->data){
		return search(root->left,data);
	}
	else{
		return search(root->right,data);
	}
}

int main(){ 
    node*root = build();
    inorder(root);
    cout<<endl;
    
    int s;
    cin>>s;
    if(search(root,s)){
    	cout<<"PRESENT";
	}
	else{
		cout<<"NOT PRESENT";
	}

return 0;
}