272. Closest Binary Search Tree Value II

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
 //use inorder it will be a increase array
public class Solution {
    public List<Integer> closestKValues(TreeNode root, double target, int k) {
        List<Integer> res = new LinkedList<Integer>();
        getClosestKValues(res, root, target, k);
        return res;
    }
    public void getClosestKValues(List<Integer> res, TreeNode root, double target, int k){
        if(root == null) return;
        getClosestKValues(res, root.left, target, k);
        if(res.size() == k){
            if(Math.abs(res.get(0) - target) > Math.abs(root.val - target)){
                res.remove(0);
                res.add(root.val);
            }
            else
                return;
        }
        else
            res.add(root.val);
        getClosestKValues(res, root.right, target, k);
    }
}