第二课主要介绍第一课余下的BFPRT算法和第二课部分内容 1.BFPRT算法详解与应用 找到第K小或者第K大的数. 普通做法:先通过堆排序然后取,是n*logn的代价. // O(N*logK) public static int[] getMinKNumsByHeap(int[] arr, int k) { if (k < 1 || k > arr.length) { return arr; } int[] kHeap = new int[k];//存放第k小的数 for (int i =…
public class Solution { public int subarraySum(int[] nums, int k) { int count = 0, pre = 0; HashMap < Integer, Integer > map = new HashMap < > (); map.put(0, 1); for (int i = 0; i < nums.length; i++) { pre += nums[i]; if (mp.containsKey(pre…
<编程之美>183页,问题2.14——求子数组的字数组之和的最大值.(整数数组) 我开始以为可以从数组中随意抽调元素组成子数组,于是就有了一种想法,把最大的元素抽出来,判断是大于0还是小于等于0,如果大于0就对除了这个最大值外剩下的数组部分进行递归: using System; using System.Collections.Generic; using System.Linq; namespace MaxSumSubArray { class Program { static void M…
You are given an integer array sorted in ascending order (may contain duplicates), you need to split them into several subsequences, where each subsequences consist of at least 3 consecutive integers. Return whether you can make such a split. Example…
You are given an integer array sorted in ascending order (may contain duplicates), you need to split them into several subsequences, where each subsequences consist of at least 3 consecutive integers. Return whether you can make such a split. Example…