Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement uses O(m + n) space, but still not the bes…

Set Matrix Zeroes (Link: https://oj.leetcode.com/problems/set-matrix-zeroes/) Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space? A straight forwar…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. 很挫的一个想法: 使用O(M+N)的space class Solution { public: void setZeroes(vector<vector<int> > &matrix) { // Start typing your C/C++ solution below // DO N…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. Follow up: Did you use extra space? A straight forward solution using O(mn) space is probably a bad idea. A simple improvement uses O(m + n) space, but stil…

Set Matrix Zeroes Total Accepted: 18139 Total Submissions: 58671My Submissions Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. 题意:给定矩阵,假设矩阵的某个位置为0.则把那一行那一列的全部元素都置为0 思路:用两个bool数组,分…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement uses O…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in-place. Example 1: Input: [   [1,1,1],   [1,0,1],   [1,1,1] ] Output: [   [1,0,1],   [0,0,0],   [1,0,1] ] Example 2: Input: [   [0,1,2,0],   [3,4,5,2],   [1,3,1,5]…

题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement us…

Set Matrix ZeroesGiven a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up:Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple im…

1. Rotate List Given a list, rotate the list to the right by k places, where k is non-negative. Example: Given 1->2->3->4->5->NULL and k = 2, return 4->5->1->2->3->NULL. 思路:这题感觉有点没有说清楚,如果k大于了链表长度该怎么办呢?这个时候怎么确定旋转位置呢?从右往左数,超出数组…

题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement us…

题目描述 给定一个 m x n 的矩阵,如果一个元素为 0,则将其所在行和列的所有元素都设为 0.请使用原地算法. 示例 1: 输入: [   [1,1,1],   [1,0,1],   [1,1,1] ] 输出: [   [1,0,1],   [0,0,0],   [1,0,1] ] 示例 2: 输入: [   [0,1,2,0],   [3,4,5,2],   [1,3,1,5] ] 输出: [   [0,0,0,0],   [0,4,5,0],   [0,3,1,0] ] 进阶: 一个直接…

给定一个 m x n 的矩阵,如果一个元素为 0,则将其所在行和列的所有元素都设为 0.请使用原地算法. 示例 1: 输入: [   [1,1,1],   [1,0,1],   [1,1,1] ] 输出: [   [1,0,1],   [0,0,0],   [1,0,1] ] 示例 2: 输入: [   [0,1,2,0],   [3,4,5,2],   [1,3,1,5] ] 输出: [   [0,0,0,0],   [0,4,5,0],   [0,3,1,0] ] 进阶: 一个直接的解决方案…

背景介绍(学习算法之前需要先了解) 射线与空间内三角形的相交检测是游戏程序设计中一个常见的问题,最典型的应用就是拾取(Picking),本文介绍一个最常见的方法,这个方法也是DirectX中采用的方法,该方法速度快,而且存储空间少.先讲述理论,然后文章末尾给出对应的代码实现与Unity中的显示. 简单而直观的方法是:先判断射线是否与三角形所在的平面相交,如果相交,再判断交点是否在三角形内.但这种方法效率并不高,因为多计算了三角形所在的平面. Möller-Trumbore射线三角相交算法是一种快…

关键词:空间几何 用途:总有地方会用到吧 文章类型:C++函数展示 @Author:VShawn(singlex@foxmail.com) @Date:2016-11-19 @Lab: CvLab202@CSU 对于空间内的两条直线A,B我假设他们一定不平行,也不相交.若已知A上两点A1.A2,B上两点B1.B2,那么可以很容易得到两条直线的方程. 然后调用函数即可解得结果: 下面提供了一个用于解决这个问题的类: #include <math.h> //用于求解两条空间直线的最近距离,以及他们…

1.7 Write an algorithm such that if an element in an MxN matrix is 0, its entire row and column are set to 0. LeetCode中的原题,请参见我之前的博客Set Matrix Zeroes 矩阵赋零.…

Set Matrix Zeroes Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple…

75. 分类颜色 我们直接按难度最高的要求做:你能想出一个仅使用常数空间的一趟扫描算法吗? 常数空间 只能扫描一趟.注意,是一趟,而不是O(n) 题中只会出现3个数字:0,1,2.换句话说,0肯定在最前面,2肯定都在后面,1都在中间 思路大概这样: 我们用双指针法,i从前往后扫,当num[i]!=0时,j从后往前扫,直到找到第一个非2的数.然后我们就需要分情况讨论了 当num[i]2 && num[j]0时,两数可以直接交换,i++然后继续 当num[i]1 && num[…

题目:Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement uses O(m + n) space, but sti…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. 思路:不能用额外空间,就用矩阵的第一行和第一列来标记这一行或这一列是否需要置0. 用两个bool量记录第一行和第一列是否需要置0 大神的代码和我的代码都是这个思路,但是我在画0的时候是行列分开处理的,大神的代码是一起处理的 void setZeroes(vector<vector<int> > &…

给定一个矩阵,把零值所在的行和列都置为零.例如: 1 2 3 1 3 1 1 1 操作之后变为 1 3 0 0 0 1 1 方法1: 赋值另存一个m*n的矩阵,在原矩阵为零的值相应置新的矩阵行和列为零.额外空间为O(m*n). 方法2: 两个数组,bool[m] 和 bool[n] 分别存某行有零,后者某列有零.之后根据数组值将原矩阵相应位置置零.额外空间O(m + n). class Solution { public: void setZeroes(vector<vector<int>…

题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. Follow up: Did you use extra space? A straight forward solution using O(mn) space is probably a bad idea. A simple improvement uses O(m + n) space, but…

题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space? A straight forward solution using O(mn) space is probably a bad idea. A simple improvement…

题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.(Medium) 分析: 题意很简单,就是把为0的元素所在的行和列都置0: 首先不能直接边循环边做,这样会造成很多本来不是0的元素被置0之后,在后续判断中将它的行列也置0: 所以简单的方法是建立两个数组,存行和列是否为0的情况,遍历一遍更新两个数组,再遍历一遍把应该置0的全部置0. 自己写的时候先考虑用了…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement uses O…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. public class Solution { public void setZeroes(int[][] matrix) { if(matrix==null){ return; } int m=matrix.length; int n=matrix[0].length; List<Integer> r=ne…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. 解题思路: 题目乍一看很简单,将矩阵当前为0的位的行列都置为0: 问题在于:当遇到一个已知0时,不能立刻将其行列置0,因为这样会把原本不是0的位更改,导致继续遍历的时候无法区分哪些是初始0,哪些是后改0: 有一个解决方法,就是先遍历所有位,记录所有初始为0的行列坐标,遍历一遍之后,再统一做更改: 但是这个解决方…

题意: 给一个n*m的矩阵,如果某个格子中的数字为0,则将其所在行和列全部置为0.(注:新置的0不必操作) 思路: 主要的问题是怎样区分哪些是新来的0? 方法(1):将矩阵复制多一个,根据副本来操作原矩阵. 方法(2):发现空间还可以用O(n)来解决. 方法(3):若m[i][j]=0,则将m[i][0]和m[0][j]标记为0,表示i行和j列都为0,但是这样的问题是,首行和首列会冲突?那就将首列先预处理一下,用另外的常量标记就行了.时间复杂度O(n*m),空间O(1). class Solut…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement uses O(m + n) space, but still…

今天看到CSDN博客的勋章换了图表,同一时候也添加显示了博客等级,看起来都听清新的,感觉不错! [题目] Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space? A straight forward solution using O(mn) sp…