Offer-8 wins the next node of the binary tree

Offer-8 wins the next node of the binary tree

Title:
Given a binary tree and a node which is, find the next node in a preorder traversal order and returns. Note that the node in the tree contains not only the left and right child nodes, the parent node contains a pointer pointing to.

Ideas:

1. The right side nodes, direct printing
2. No node on the right side
   1. Left parent node of this node is own print
   2. Right parent node of this node is yourself, keep looking up, until the meet 2.1

Own answer:

/*
public class TreeLinkNode {
    int val;
    TreeLinkNode left = null;
    TreeLinkNode right = null;
    TreeLinkNode next = null;

    TreeLinkNode(int val) {
        this.val = val;
    }
}
*/
public class Solution {
    public TreeLinkNode GetNext(TreeLinkNode pNode)
    {
        if(pNode == null) return null;
        TreeLinkNode next = null;
        if(pNode.right != null){
            TreeLinkNode pRight = pNode.right;            
            while(pRight.left != null)
                pRight = pRight.left;
            next = pRight;
        }else if(pNode.next != null){
            TreeLinkNode curNode = pNode;
            TreeLinkNode pParrent = pNode.next;
            while(pParrent != null && pParrent.right == curNode){
                curNode = pParrent;
                pParrent = pParrent.next;
            }
            next = pParrent;
        }
        return next;        
    }
}

Mistakes:

note:

Someone to answer: