原题地址:https://oj.leetcode.com/problems/set-matrix-zeroes/ 题意: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:分别记录两个向量x, y,保存行和列是否有0,再次遍历数组时查询对应的行和列然后修改值. 代码: class Solution: # @param matrix, a list of…

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…

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…

原题地址:https://oj.leetcode.com/problems/spiral-matrix-ii/ 题意: Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. For example,Given n = 3, You should return the following matrix: [ [ 1, 2, 3 ], [ 8, 9, 4 ], […

http://oj.leetcode.com/problems/set-matrix-zeroes/ 因为空间要求原地,所以一些信息就得原地存储.使用第一行第一列来存本行本列中是否有0.另外对于第一个元素[0][0],需要额外处理. #include <iostream> #include <vector> using namespace std; class Solution { public: void setZeroes(vector<vector<int>…

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. 原题链接:https://oj.leetcode.com/problems/set-matrix-zeroes/ 题目:给定一个m * n 的矩阵.假设有一个元素是0.将其所在行和列设为0. 思路:先记录下是0 的元素的位置.再去置0. public void setZeroes(int[][] matrix)…

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…

题目: Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements. For example, given nums = [0, 1, 0, 3, 12], after calling your function, nums should be [1, 3, 12, 0, 0]. python…

Factorial Trailing Zeroes Given an integer n, return the number of trailing zeroes in n!. 题目意思: n求阶乘以后,其中有多少个数字是以0结尾的. 方法一: class Solution: # @return an integer def trailingZeroes(self, n): res = 0 if n < 5: return 0 else: return n/5+ self.trailingZe…

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(m n) space is probably a bad idea.A simple improvement uses…

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…

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…

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…

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…

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.…

LeetCode初级算法的Python实现--数组 # -*- coding: utf-8 -*- """ @Created on 2018/6/3 17:06 @author: ZhifengFang """ # 排列数组删除重复项 def removeDuplicates(nums): if len(nums) <= 1: return len(nums) i = 1 while len(nums) != i: if nums[i] =…

[leetcode]Word Ladder II @ Python 原题地址:http://oj.leetcode.com/problems/word-ladder-ii/ 参考文献:http://blog.csdn.net/doc_sgl/article/details/13341405   http://chaoren.is-programmer.com/ 题意:给定start单词,end单词,以及一个dict字典.要求找出start到end的所有最短路径,路径上的每个单词都要出现在dict…

Spiral Matrix IIGiven an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. For example,Given n = 3, You should return the following matrix:[ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ]] SOLUTION 1: 还是与上一题Spiral Matrix类似…

LeetCode初级算法的Python实现--排序和搜索.设计问题.数学及其他 1.排序和搜索 class Solution(object): # 合并两个有序数组 def merge(self, nums1, m, nums2, n): """ :type nums1: List[int] :type m: int :type nums2: List[int] :type n: int :rtype: void Do not return anything, modify…

LeetCode初级算法的Python实现--链表 之前没有接触过Python编写的链表,所以这里记录一下思路.这里前面的代码是和leetcode中的一样,因为做题需要调用,所以下面会给出. 首先定义链表的节点类. # 链表节点 class ListNode(object): def __init__(self, x): self.val = x # 节点值 self.next = None 其次分别定义将列表转换成链表和将链表转换成字符串的函数: # 将列表转换成链表 def stringTo…

LeetCode初级算法的Python实现--字符串 # 反转字符串 def reverseString(s): return s[::-1] # 颠倒数字 def reverse(x): if x < 0: flag = -2 ** 31 result = -1 * int(str(x)[1:][::-1]) if result < flag: return 0 else: return result else: flag = 2 ** 31 - 1 result = int(str(x)[…

文章目录 Hash表简介 基本思想 建立步骤 问题 Hash表实现 Hash函数构造 冲突处理方法 leetcode两数之和python实现 题目描述 基于Hash思想的实现 Hash表简介 基本思想 哈希存储的基本思想是根据当前待存储数据的特征,以记录关键字(key)为自变量,设计一个哈希函数Hash,根据Hash计算出对应的函数值Hash(key),以这个值(哈希地址)作为数据元素的地址,并将数据元素存入到相应地址的存储单元中.按照这个思想构造的表就叫做哈希表(Hash table,也叫散列…

题目来源: https://leetcode.com/problems/set-matrix-zeroes/ 题意分析: 输入一个m×n矩阵,如果出现有0,那么将对应的行和列都变成0. 题目思路: 简单的一个想法是记录行列哪些出现过0,那么将其对应到的行列转成0. 代码(Python): class Solution(object): def setZeroes(self, matrix): """ :type matrix: List[List[int]] :rtype:…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 原地操作 新建数组 队列 日期 题目地址:https://leetcode.com/problems/set-matrix-zeroes/description/ 题目描述 Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in-pl…

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: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. 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]…

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> > &…

原题链接: http://oj.leetcode.com/problems/set-matrix-zeroes/ 这是一个矩阵操作的题目,目标非常明白,就是假设矩阵假设有元素为0,就把相应的行和列上面的元素都置为0.这里最大的问题就是我们遇到0的时候不能直接把矩阵的行列在当前矩阵直接置0,否则后面还没訪问到的会被当成原来是0,最后会把非常多不该置0的行列都置0了.一个直接的想法是备份一个矩阵,然后在备份矩阵上推断,在原矩阵上置0,这样当然是能够的,只是空间复杂度是O(m*n),不是非常理想.上面…

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>…