Check for Children Sum Property in a Binary Tree

Run

class Node {
    int data;
    Node left, right;

    public Node(int d) {
        data = d;
        left = right = null;
    }
}

class BinaryTree {
    Node root;

    /* returns 1 if children sum property holds for the given
    node and both of its children*/
    int isSumProperty(Node node) {

        /* left_data is left child data and right_data is for right
           child data*/
        int left_data = 0, right_data = 0;

        /* If node is NULL or it's a leaf node then
        return true */
        if (node == null ||
            (node.left == null && node.right == null))
            return 1;
        else {

            /* If left child is not present then 0 is used
               as data of left child */
            if (node.left != null)
                left_data = node.left.data;

            /* If right child is not present then 0 is used
               as data of right child */
            if (node.right != null)
                right_data = node.right.data;

            /* if the node and both of its children satisfy the
               property return 1 else 0*/
            if ((node.data == left_data + right_data) &&
                (isSumProperty(node.left) != 0) &&
                isSumProperty(node.right) != 0)
                return 1;
            else
                return 0;
        }
    }
}
public class Main1{

    /* driver program to test the above functions */

    public static void main(String[] args) {
        BinaryTree tree = new BinaryTree();
        tree.root = new Node(10);
        tree.root.left = new Node(8);
        tree.root.right = new Node(2);
        tree.root.left.left = new Node(3);
        tree.root.left.right = new Node(5);
        tree.root.right.right = new Node(2);
        if (tree.isSumProperty(tree.root) != 0)
            System.out.println("The given tree satisfies children" +
                " sum property");
        else
            System.out.println("The given tree does not satisfy children" +
                " sum property");
    }
}