Given n points on a 2D plane, find if there is such a line parallel to y-axis that reflect the given set of points. Example 1: Given points = [[1,1],[-1,1]], return true. Example 2: Given points = [[1,1],[-1,-1]], return false. Follow up: Could you d…

Given n points on a 2D plane, find if there is such a line parallel to y-axis that reflect the given points. Example 1: Given points = [[1,1],[-1,1]], return true. Example 2: Given points = [[1,1],[-1,-1]], return false. Follow up: Could you do bette…

题目 //数学题//直线 y = k * x + b//直线 ax+by+c=0; 点 (x0,y0); 点到直线距离 d = (ax0+by0+c)/sqrt(a^2+b^2) /******************************************************************关于直线对称公式如下: 1.点(a,b)关于直线 y=kx+m (k=1或-1)的对称点为:(b/k-m/k,ka+m),实际上是将表达式中的x,y的值互换,因为直线方程 y=kx+m…

LeetCode 5 最长对称串 最早时候做这道题的时候还是用Java写的,用的是字符串匹配的思路,一直Time Limit Exceeded.甚至还想过用KMP开优化子串查找. public class Solution { public String longestPalindrome(String s) { String reverseS = new StringBuilder(s).reverse().toString(); String maxMatch = ""; for…

Leetcode:面试题28. 对称的二叉树 Leetcode:面试题28. 对称的二叉树 Talk is cheap . Show me the code . /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * };…

Given n points on a 2D plane, find if there is such a line parallel to y-axis that reflect the given set of points. Example 1: Given points = [[1,1],[-1,1]], return true. Example 2: Given points = [[1,1],[-1,-1]], return false. Follow up:Could you do…

Given n points on a 2D plane, find if there is such a line parallel to y-axis that reflect the given points. Example 1: Given points = [[1,1],[-1,1]], return true. Example 2: Given points = [[1,1],[-1,-1]], return false. Follow up:Could you do better…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to count the total strobogrammatic numbers that exist in the range of low <= num <= high. For example,Given low = "50&qu…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Find all strobogrammatic numbers that are of length = n. For example,Given n = 2, return ["11","69","88","96"…

7.3 Given two lines on a Cartesian plane, determine whether the two lines would intersect. 这道题说是在笛卡尔坐标系中,让我们确定两条直线是否相交. 那么我们首先要写个直线的类来表示直线,最常见的表示方法为y=kx+b,k为斜率,b为与y轴的交点,然后我们来考虑什么情况下两条直线会相交,首先,如果两条直线完全重合的话,应该也算是相交的,其次如果两条直线不平行的话,那么也是相交的,那么我们判断相交条件主要基于…

There is a special square room with mirrors on each of the four walls.  Except for the southwest corner, there are receptors on each of the remaining corners, numbered 0, 1, and 2. The square room has walls of length p, and a laser ray from the south…

题目大意 #!/usr/bin/env python # coding=utf-8 # Date: 2018-08-30 """ https://leetcode.com/problems/symmetric-tree/description/ 101. Symmetric Tree Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). Fo…

这道题是LeetCode里的第101道题.是我在学数据结构——二叉树的时候碰见的题. 题目如下: 给定一个二叉树,检查它是否是镜像对称的. 例如,二叉树 [1,2,2,3,4,4,3] 是对称的. 1 / \ 2 2 / \ / \ 3 4 4 3 但是下面这个 [1,2,2,null,3,null,3] 则不是镜像对称的: 1 / \ 2 2 \ \ 3 3 说明: 你可以运用递归和迭代两种方法解决这个问题. 解题思路: 读完题目后我首先想到的是用遍历的方法来解题,树的遍历有三种:前序遍历,中…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to determine if a number is strobogrammatic. The number is represented as a string. For example, the numbers "69", "…

Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree is symmetric: 1 / \ 2 2 / \ / \ 3 4 4 3 But the following is not: 1 / \ 2 2 \ \ 3 3 Note:Bonus points if you could solve it b…

首先找到X方向的中点,如果中点是一个点,那么分别从这个点开始往左右找就行:如果是一个区间,比如1 2之间,那么首先总点数得是偶数,然后以1和2往左右两边找就行.. 找的时候,有3种情况: 同时没找到,继续: 一个找到,一个没找到,FALSE: 同时找到,左边找到的每个点,必须对应一个右边找到的每个点,纵坐标相同. 所以构架的时候,我用的 Map public class Solution { public boolean isReflected(int[][] points) { Map<Int…

给定一个二维平面,平面上有 n 个点,求最多有多少个点在同一条直线上. 示例 1: 输入: [[1,1],[2,2],[3,3]] 输出: 3 解释: ^ | |        o |     o |  o   +-------------> 0  1  2  3 4 示例 2: 输入: [[1,1],[3,2],[5,3],[4,1],[2,3],[1,4]] 输出: 4 解释: ^ | | o |     o   o |      o |  o   o +------------------…

Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree [1,2,2,3,4,4,3] is symmetric: 1 / \ 2 2 / \ / \ 3 4 4 3 But the following [1,2,2,null,3,null,3] is not: 1 / \ 2 2 \ \ 3 3 Not…

Given n points on a 2D plane, find the maximum number of points that lie on the same straight line. 这道题给了我们一堆二维点,然后让我们求最大的共线点的个数,根据初中数学我们知道,两点确定一条直线,而且可以写成y = ax + b的形式,所有共线的点都满足这个公式.所以这些给定点两两之间都可以算一个斜率,每个斜率代表一条直线,对每一条直线,带入所有的点看是否共线并计算个数,这是整体的思路.但是还有…

7.6 Given a two-dimensional graph with points on it, find a line which passes the most number of points. 这道题给了我们许多点,让我们求经过最多点的一条直线.给之前那道7.5 A Line Cut Two Squares in Half 平均分割两个正方形的直线一样,都需要自己写出点类和直线类.在直线类中,我用我们用斜率和截距来表示直线,为了应对斜率不存在情况,我们还需用一个flag来标记是否…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Find all strobogrammatic numbers that are of length = n. For example,Given n = 2, return ["11","69","88","96"…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to count the total strobogrammatic numbers that exist in the range of low <= num <= high. For example,Given low = "50&qu…

[2]Add Two Numbers (2018年12月23日,review) 链表的高精度加法. 题解:链表专题:https://www.cnblogs.com/zhangwanying/p/9797184.html [7]Reverse Integer (2018年12月23日, review) 给了一个32位的整数,返回它的reverse后的整数.如果reverse后的数超过了整数的范围,就返回 0. Example 1: Input: 123 Output: 321 Example 2:…

[1]Two Sum (2018年11月9日,k-sum专题,算法群衍生题) 给了一个数组 nums, 和一个 target 数字,要求返回一个下标的 pair, 使得这两个元素相加等于 target . 题解:我这次最大范围的优化代码, hash-table + one pass,时间复杂度 O(N),空间复杂度 O(N).重点在于动态找,一边生成hash-table的同时去找答案,不是先生成hash-table再开始找答案. //这种类似 hash 的能用 unordered_map 就不要…

终于将LeetCode的免费题刷完了,真是漫长的第一遍啊,估计很多题都忘的差不多了,这次开个题目汇总贴,并附上每道题目的解题连接,方便之后查阅吧~ 477 Total Hamming Distance 44.10% Meidum 475 Heaters  30.20% Easy 474 Ones and Zeroes  34.90% Meidum 473 Matchsticks to Square  31.80% Medium 472 Concatenated Words 29.20% Hard…

突然很想刷刷题,LeetCode是一个不错的选择,忽略了输入输出,更好的突出了算法,省去了不少时间. dalao们发现了任何错误,或是代码无法通过,或是有更好的解法,或是有任何疑问和建议的话,可以在对应的随笔下面评论区留言,我会及时处理,在此谢过了. 过程或许会很漫长,也很痛苦,慢慢来吧. 编号 题名 过题率 难度 1 Two Sum 0.376 Easy 2 Add Two Numbers 0.285 Medium 3 Longest Substring Without Repeating C…

All LeetCode Questions List(Part of Answers, still updating) 题目汇总及部分答案(持续更新中) Leetcode problems classified by company 题目按公司分类(Last updated: October 2, 2017) .   Top Interview Questions # Title Difficulty Acceptance 1 Two Sum Medium 17.70% 2 Add Two N…

All LeetCode Questions List 题目汇总 Sorted by frequency of problems that appear in real interviews. Last updated: October 2, 2017Google (214)534 Design TinyURL388 Longest Absolute File Path683 K Empty Slots340 Longest Substring with At Most K Distinct C…

终于将LeetCode的免费题刷完了,真是漫长的第一遍啊,估计很多题都忘的差不多了,这次开个题目汇总贴,并附上每道题目的解题连接,方便之后查阅吧~ 如果各位看官们,大神们发现了任何错误,或是代码无法通过OJ,或是有更好的解法,或是有任何疑问,意见和建议的话,请一定要在对应的帖子下面评论区留言告知博主啊(如果不方便注册博客园的话,可以下载下文提到的APP,在Feedback中给博主发邮件交流哈),同时也请大家踊跃地,大量地,盲目地提供各个题目的follow up一起讨论哈,多谢多谢,祝大家刷得愉快…

实现目的:有一系列的点,需要拟合出一条直线. cv::fitLine()的具体调用形式如下: void cv::fitLine( cv::InputArray points, // 二维点的数组或vector cv::OutputArray line, // 输出直线,Vec4f (2d)或Vec6f (3d)的vector int distType, // 距离类型 double param, // 距离参数 double reps, // 径向的精度参数 表示直线到原点距离的精度,建议取 0…