题解 | #二叉树的下一个结点#

/*
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) {
            TreeLinkNode node = pNode.right;
            while (node.left != null){
                node = node.left;
            }
            return node;
        } else {
            while (pNode.next != null) {
                TreeLinkNode parent = pNode.next;
                if (parent.left == pNode){
                    return parent;
                }
                pNode = pNode.next;
            }
        }
        return null;
    }
}