摘要：
方法一：树状数组 class NumArray { int[] nums; int[] bitArr; int n; public NumArray(int[] nums) { n = nums.length; this.nums = nums; bitArr = new int[n+1]; for 阅读全文
摘要：
class Solution { public List<Integer> findMinHeightTrees(int n, int[][] edges) { List<Integer> res = new ArrayList<>(); if (n == 1) { res.add(0); retu 阅读全文