1 /**
 2  * Definition for a binary tree node.
 3  * public class TreeNode {
 4  *     int val;
 5  *     TreeNode left;
 6  *     TreeNode right;
 7  *     TreeNode(int x) { val = x; }
 8  * }
 9  */
10 class Solution { 
11     static int count=0;
12     static int res=0;
13     public int kthLargest(TreeNode root, int k) {
14      count=0;
15      max_k(root,k);
16      return res;
17     }
18     public static void  max_k(TreeNode root,int k){
19             //考察第k大的，先进右子树，第k小的，进左子树先   count!=k,条件时避免已经找到还继续递归下去
20             if(count!=k&&root.right!=null){
21                 max_k(root.right,k);
22             }
23             //判断当前结点是否时第k大
24             if(count!=k){
25                 count++;
26                 if(count==k){
27                     res=root.val;
28                 }
29             }
30          
31             if(count!=k&&root.left!=null){
32                 max_k(root.left,k);
33             }
34             
35         
36     }
37 }