package easy;

import tree.TreeNode;


public class KthSmallest {
    private TreeNode tarNode;
    private int t_k;
    public int kthSmallest(TreeNode root, int k) {
        //二叉树搜索树：左小右大
        t_k=k;
        inOrder(root);
        return tarNode.val;
    }

    private void inOrder(TreeNode root) {
        if (t_k==0){
            return;
        }

        if (root.left!=null){
            inOrder(root.left);
        }
        t_k--;
        if (t_k==0){
            tarNode=root;
            return;
        }
        if (root.right!=null){
            inOrder(root.right);
        }
    }
}

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