import java.util.*; /* * public class TreeNode { * int val = 0; * TreeNode left = null; * TreeNode right = null; * public TreeNode(int val) { * this.val = val; * } * } */ public class Solution { /** * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可 * * * @param root TreeNode类 * @param target double浮点型 * @param m int整型 * @return int整型一维数组 */ public int[] findClosestElements (TreeNode root, double target, int m) { // write code here List<Integer> list = new ArrayList<>(); Deque<TreeNode> dq = new ArrayDeque<>(); dq.offer(root); //遍历每一个树节点的值,存入链表中 while(!dq.isEmpty()){ TreeNode cur = dq.poll(); list.add(cur.val); if(cur.left != null){ dq.offer(cur.left); } if(cur.right != null) dq.offer(cur.right); } //按照和target的距离从小到大排序 Collections.sort(list, (a, b) -> { if(Math.abs(a - target) > Math.abs(b - target)){ return 1; } else if(Math.abs(a - target) < Math.abs(b - target)){ return -1; } return 0; }); int[] ans = new int[m]; //取出链表前m个数并排序,即为答案 for(int i = 0; i < m; i++) ans[i] = list.get(i); Arrays.sort(ans); return ans; } }