Pair with given sum in BST Java

PROGRAM TO FIND A PAIR WITH GIVEN SUM IN BST

import java.util.*;

 

class GFG {

 

    static class Node {

        int data;

        Node left, right;

    };

 

    static Node NewNode(int data)

    {

        Node temp = new Node();

        temp.data = data;

        temp.left = null;

        temp.right = null;

        return temp;

    }

 

    static Node insert(Node root, int key)

    {

        if (root == null)

            return NewNode(key);

        if (key < root.data)

            root.left = insert(root.left, key);

        else

            root.right = insert(root.right, key);

        return root;

    }

 

    static boolean findpairUtil(Node root, int sum,

                                HashSet<Integer> set)

    {

        if (root == null)

            return false;

 

        if (findpairUtil(root.left, sum, set))

            return true;

 

        if (set.contains(sum - root.data)) {

            System.out.println("Pair is found ("

                               + (sum - root.data) + ", "

                               + root.data + ")");

            return true;

        }

        else

            set.add(root.data);

 

        return findpairUtil(root.right, sum, set);

    }

 

    static void findPair(Node root, int sum)

    {

        HashSet<Integer> set = new HashSet<Integer>();

        if (!findpairUtil(root, sum, set))

            System.out.print("Pairs do not exit"

                             + "\n");

    }

 

    // Driver code

    public static void main(String[] args)

    {

        Node root = null;

        root = insert(root, 15);

        root = insert(root, 10);

        root = insert(root, 20);

        root = insert(root, 8);

        root = insert(root, 12);

        root = insert(root, 16);

        root = insert(root, 25);

        root = insert(root, 10);

 

        int sum = 33;

        findPair(root, sum);

    }

}




OUTPUT:

Pair is found (8, 25)

CREDITS: https://www.geeksforgeeks.org/find-pair-given-sum-bst/