JAVA program to print ancestors of a node in a BST

ALGORITHM:

 To print ancestors of a node in a BST , we just add a print function to the searching function of a BST before the recursion.

Steps in a search function of BST:

1. if current node is the required node print the node
2. if current node is greater than required node goto step 1 for left subtree
3. if current node is lesser than required node goto step 1 for right subtree

CODE:

//utility class for node

public class node{
    public int data;
    public node left,right;
    public node(){
        data=0;
        left=right=null;
    }
}

//class to implement the algorithm
import java.util.Scanner;

public class ancestorsNode {

    static Scanner in =new Scanner(System.in);
   
    static node inputTree(){
        node temp=new node();
        System.out.print("Enter the value: ");
        temp.data=in.nextInt();
        System.out.print("Enter y if the node "+temp.data+" has left subtree: ");
        if(in.next().charAt(0)=='y')
            temp.left=inputTree();
        else
            temp.left=null;
        System.out.print("Enter y if the node "+temp.data+" has right subtree: ");
        if(in.next().charAt(0)=='y')
            temp.right=inputTree();
        else
            temp.right=null;
        return temp;
    }

    static void inorder(node tree){
        if(tree==null)
            return;
        inorder(tree.left);
        System.out.print(tree.data+"\t");
        inorder(tree.right);
    }

    public static void printAnc(node tree,int nod){

        if(nod==tree.data){
            System.out.println(nod);
            return;
        }
        System.out.print(tree.data+"---");
        if(nod<tree.data)
            printAnc(tree.left,nod);
       
        else
            printAnc(tree.right,nod);
    }

    public static void main(String[] args) {
        node tree=new node();
        System.out.print("Enter y if tree is null: ");
        if(in.next().charAt(0)=='y')
            tree=null;
        else
            tree=inputTree(tree);
        System.out.print("Inorder traversal of the tree is:\n");
        inorder(tree);
        System.out.print("\nEnter the node:");
        int nd = in.nextInt();
        printAnc(tree,nd);
        in.close();
    }
}

OUTPUT:

Enter y if tree is null: n
Enter the value: 5
Enter y if the node 5 has left subtree: y
Enter the value: 3
Enter y if the node 3 has left subtree: y
Enter the value: 2
Enter y if the node 2 has left subtree: n
Enter y if the node 2 has right subtree: n
Enter y if the node 3 has right subtree: y
Enter the value: 4
Enter y if the node 4 has left subtree: n
Enter y if the node 4 has right subtree: n
Enter y if the node 5 has right subtree: y
Enter the value: 7
Enter y if the node 7 has left subtree: y
Enter the value: 6
Enter y if the node 6 has left subtree: n
Enter y if the node 6 has right subtree: n
Enter y if the node 7 has right subtree: y
Enter the value: 8
Enter y if the node 8 has left subtree: n
Enter y if the node 8 has right subtree: n
Inorder traversal of the tree is:
2    3    4    5    6    7    8    

Enter the node:8
5---7---8