Populating Next Right Pointers in Each Node II

 1 public class Solution {
 2     public void connect(TreeLinkNode root) {
 3         TreeLinkNode left = root;
 4         while(left!=null){
 5             TreeLinkNode across = left;
 6             TreeLinkNode leftMost = null;
 7             while(across!=null){
 8                 if(across.left!=null){
 9                     if(leftMost==null)
10                         leftMost = across.left;
11                     across.left.next = findNextRight(across,true);
12                 }
13                 if(across.right!=null){
14                     if(leftMost==null)
15                         leftMost = across.right;
16                     across.right.next = findNextRight(across,false);
17                 }
18                 across = across.next;
19             }
20             left = leftMost;
21         }
22     }
23     public TreeLinkNode findNextRight(TreeLinkNode root,boolean isLeft){
24         if(isLeft){
25             if(root.right!=null) return root.right;
26         }
27         root = root.next;
28         while(root!=null){
29             if(root.left!=null)
30                 return root.left;
31             if(root.right!=null)
32                 return root.right;
33             root = root.next;
34         }
35         return null;
36     
37     }
38 }