Print nodes at k distance from root

Given a root of a tree, and an integer k. Print all the nodes which are at k distance from root.

For example, in the below tree, 4, 5 & 8 are at distance 2 from root.

            1
          /   \
        2      3
      /  \    /
    4     5  8 

// Java program to print nodes at k distance from root    /* A binary tree node has data, pointer to left child    and a pointer to right child */ class Node {     int data;     Node left, right;        Node(int item)     {         data = item;         left = right = null;     } }    class BinaryTree {     Node root;        void printKDistant(Node node, int k)     {         if (node == null)             return;         if (k == 0)         {             System.out.print(node.data + " ");             return;         }         else         {             printKDistant(node.left, k - 1);             printKDistant(node.right, k - 1);         }     }           /* Driver program to test above functions */     public static void main(String args[]) {         BinaryTree tree = new BinaryTree();                   /* Constructed binary tree is                 1               /   \              2     3             /  \   /            4    5 8         */         tree.root = new Node(1);         tree.root.left = new Node(2);         tree.root.right = new Node(3);         tree.root.left.left = new Node(4);         tree.root.left.right = new Node(5);         tree.root.right.left = new Node(8);            tree.printKDistant(tree.root, 2);     } }