Next Right Pointer O(1)

NextRightPointer2.java

package com.interviewbytes.trees;

public class NextRightPointer2 {

    public void connect(TreeLinkNode root) {

        TreeLinkNode start = root;

        while (start != null) {
            TreeLinkNode current = start;
            while (current != null) {
                if (current.left != null) current.left.next = current.right;
                if (current.right != null && current.next != null) current.right.next = current.next.left;
                current = current.next;
            }
            start = start.left;
        }
    }
}

TreeLinkNode.java

package com.interviewbytes.trees;

public class TreeLinkNode {

    int val;

    TreeLinkNode left, right, next;

    TreeLinkNode(int x) {
        val = x;
    }
}