find the node in k distance in a given tree list, solution 1 : shifting -> complexity = o (n)

gistfile1.java

public class HelloWorld {

    public static void main(String[] args) {
        Node r = new Node(0);

        r.left = new Node(1);
        r.right = new Node(2);

        r.left.left = new Node(3);
        r.left.right = new Node(4);
        r.left.left.left = new Node(5);

        r.right.right = new Node(6);
        r.right.left = new Node(7);
        r.right.left.right = new Node(8);


        find(r, 2, null, -1);
    }

    public static class Node {
        Node parent;
        Node left;
        Node right;
        int value;

        public Node(int value) {
            this.value = value;
        }

    }


    public static void find(Node n, int k, int[] list, int last) {

        if (list == null) {
            list = new int[k];
            for (int i = 0; i < k; i++) {
                list[i] = -1;
            }
        }


        if (n.left == null && n.right == null) {
            System.out.println("\nleaf : " + n.value);
            if (list[k - 1] != -1) {
                int i = last + 1 == k ? 0 : last + 1;
                System.out.println("node in k distance : " + list[i]);
            }
        }

        if (n.left != null) {

            n.left.parent = n;
            int[] temp = new int[k];
            temp = list.clone();
            int templast = getLastIndex(temp, last, k, n.value);
            find(n.left, k, temp, templast);
        }

        if (n.right != null) {

            n.right.parent = n;
            int[] temp = new int[k];
            temp = list.clone();
            int templast = getLastIndex(temp, last, k, n.value);

            find(n.right, k, temp, templast);
        }



    }

    private static int getLastIndex(int[] temp, int last, int k, int value) {
        int templast = last;
        if (templast + 1 < k) {
            temp[templast + 1] = value;

            templast++;
        } else {
            temp[templast + 1 - k] = value;
            templast = templast + 1 - k;
        }

        return templast;
    }




}