剑指offer 8 二叉树的下一节点

/*
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.right!=null){
            pNode=pNode.right;
            while(pNode.left!=null){
                pNode=pNode.left;
            }
            return pNode;
        }
        
        else{
            while(pNode.next!=null){
                TreeLinkNode parentNode=pNode.next;
                if(parentNode.left==pNode)
                    return parentNode;
                else{
                    pNode=pNode.next;
                }
            }
            return null;//这儿错了 之前写的pNode
        }
        
    }
}