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求逆序对的个数特点：利用归并排序中合并的步骤，计算逆序对int merge_inversion(int *arr,int start,int end,int middle);int count_inversion(int *arr,int start,int end){ if(start<end) { int middle = (start + end)/2; int left = count_inversion(arr,start,middle

二分查找特点：T(n) = T(n/2 - 1) + c时间复杂度O（lgn)前提：需要已排序的集合int binary_search(int *arr,int start,int end,int key){ if(start<end) { int middle = (start+end)/2; if(arr[middle] == key) return middle; if(key<arr[middle-1])

二分搜索<2>找出最大值和第二大值，时间复杂度O（n）class Program { static void Main(string[] args) { List<int> list = new List<int> { 10, 3, 6, 4, 7, 1, 9, 2 }; var v = getMax(list, 0, list.Count - 1); }

二分搜索问题找出最大值和最小值 时间复杂度O（n）using System;using System.Collections.Generic;namespace dataLearn{ class Program { static void Main(string[] args) { List<int> list = new List<int> { 10, 3, 6, 4, 7, 1, 9, 2 };

归并排序特点：非原址排序，比较排序，时间复杂度O（nlogn）//// Created by 许加权 on 2021/6/18.//#include <iostream>void merge_sort(int *arr,int start,int end){ if(start != end) { int middle = (start + end)/2; merge_sort(arr,start,middle); m

using System;using System.Collections.Generic;namespace dataLearn{struct Coordinate{public float x;public float y;public Coordinate(float x,float y){this.x = x;this.y = y;}public override string ToString(){return $“x:{x},y:{y}”;}public voi

连续项的最大和问题using System;using System.Collections.Generic;namespace dataLearn{ class Program { static void Main(string[] args) { List<int> list1 = new List<int> { -2, 4, -1, 3, 5, -6, 1, 2 }; Li