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// @Title: 二叉搜索树的第k大节点 (二叉搜索树的第k大节点  LCOF)
// @Author: 15816537946@163.com
// @Date: 2022-02-19 14:11:32
// @Runtime: 8 ms
// @Memory: 6.1 MB
/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func kthLargest(root *TreeNode, k int) int {
    var dfs func(*TreeNode)
    var ans int
    dfs = func(node *TreeNode) {
        if node == nil {
            return 
        }

        dfs(node.Right)
        if k-=1;k == 0 {
            ans = node.Val
            return 
        }
        dfs(node.Left)
    }
    
    dfs(root)
    return ans

}