二分查找 1.二分查找的时间复杂度分析: 二分查找每次排除掉一半不合适的值,所以对于n个元素的情况来说: 一次二分剩下:n/2 两次:n/4 m次:n/(2^m) 最坏情况是排除到最后一个值之后得到结果,所以:n/(2^m) = 1 2^m = n 所以时间复杂度为:log2(n) 2.二分查找的实现方法: (1)递归 int RecursiveBinSearch(int arr[], int bottom, int top, int key) { if (bottom <= top) { in…

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each row is greater than the last integer of the previous ro…

74. 搜索二维矩阵 74. Search a 2D Matrix 题目描述 编写一个高效的算法来判断 m x n 矩阵中,是否存在一个目标值.该矩阵具有如下特性: 每行中的整数从左到右按升序排列. 每行的第一个整数大于前一行的最后一个整数. LeetCode74. Search a 2D Matrix中等 示例 1: 输入: matrix = [   [1, 3, 5, 7],   [10, 11, 16, 20],   [23, 30, 34, 50]] target = 3 输出: tru…

本文始发于个人公众号:TechFlow,原创不易,求个关注 今天是LeetCode专题43篇文章,我们今天来看一下LeetCode当中的74题,搜索二维矩阵,search 2D Matrix. 这题的官方难度是Medium,通过率是36%,和之前的题目不同,这题的点赞比非常高,1604个赞,154个反对.可见这题的质量还是很高的,事实上也的确如此,这题非常有意思. 题意 这题的题意也很简单,给定一个二维的数组matrix和一个整数target,这个数组当中的每一行和每一列都是递增的,并且还满足每…

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each row is greater than the last integer of the previous ro…

74. Search a 2D Matrix 整个二维数组是有序排列的,可以把这个想象成一个有序的一维数组,然后用二分找中间值就好了. 这个时候需要将全部的长度转换为相应的坐标,/col获得x坐标,%col获得y坐标 class Solution { public: bool searchMatrix(vector<vector<int>>& matrix, int target) { int row = matrix.size(); ) return false; ].s…

74. 搜索二维矩阵 编写一个高效的算法来判断 m x n 矩阵中,是否存在一个目标值.该矩阵具有如下特性: 每行中的整数从左到右按升序排列. 每行的第一个整数大于前一行的最后一个整数. 示例 1: 输入: matrix = [ [1, 3, 5, 7], [10, 11, 16, 20], [23, 30, 34, 50] ] target = 3 输出: true 示例 2: 输入: matrix = [ [1, 3, 5, 7], [10, 11, 16, 20], [23, 30, 34…

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each row is greater than the last integer of the previous ro…

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each row is greater than the last integer of the previous ro…

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each row is greater than the last integer of the previous ro…