Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. Credits:Special thanks to @Freezen for adding this pr…

在一个由0和1组成的二维矩阵内,寻找只包含1的最大正方形,并返回其面积.例如,给出如下矩阵:1 0 1 0 01 0 1 1 11 1 1 1 11 0 0 1 0返回 4. 详见:https://leetcode.com/problems/maximal-square/description/ Java实现: 建立一个二维dp数组,其中dp[i][j]表示到达(i, j)位置所能组成的最大正方形的边长.首先考虑边界情况,也就是当i或j为0的情况,那么在首行或者首列中,必定有一个方向长度为1,那…

问题描述: 题目链接:221 Maximal Square 问题找解决的是给出一个M*N的矩阵, 只有'1', '0',两种元素: 需要你从中找出 由'1'组成的最大正方形.恩, 就是这样. 我们看到, 这道题目的标签还是DP, 那么问题的关键就是要找到一个符合判断是否为正方形的递推式. 老套路, 先看基本型, 对于一个2*2的正方形,对于右下角的元素(1,1)而言, 他的上(0,1), 左(1,0), 左上(0,0)三个元素应该都是'1', 如此才能够组成一个合规的正方形: 那么如果是一个3*…

本来也想像园友一样,写一篇总结告别 2015,或者说告别即将过去的羊年,但是过去一年发生的事情,实在是出乎平常人的想象,也不具有代表性,于是计划在今年 6 月份写一篇 "半年总结",希望不会忘记.羊年,还是以一道有意思的算法题来告别吧! Maximal Square,又是一道有意思的题.给出一个二维数组,数组中的元素是 1 或者 0,求解最大的由 1 组成的正方形面积. 比如这样一个二维数组: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 很显然最大的…

Maximal Square Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example: Input: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 Output: 4 解 动态规划,设\(dp[i][j]\)表示下标为(i, j)的左上角区域的最大正方形面积,当\(\math…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. Have you met this question in a real interview?     Example For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0…

Maximal Square Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. Credits:Special thanks to @Freezen for…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. class Solution { public: inline int min(int x, int y…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. Credits:Special thanks to @Freezen for adding this pr…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. Credits:Special thanks to @Freezen for adding this pr…

题目: Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. 链接: http://leetcode.com/problems/maximal-square/…

题目说明 Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 Return 4. 题目分析 我采用的方法比较笨拙,就是对于矩阵中的每一个元素,以反"L"…

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 动态规划 日期 题目地址: https://leetcode.com/problems/maximal-square/description/ 题目描述 Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and r…

本题用brute force超时.可以用DP,也可以不用. dp[i][j] 代表 以(i,j)为右下角正方形的边长. class Solution(object): def maximalSquare(self, matrix): """ :type matrix: List[List[str]] :rtype: int """ if not matrix: return 0 m = len(matrix) n = len(matrix[0])…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. 解题思路: dp问题,用一个dp[i][j]保存matrix[i][j]作为右下节点的时候的最大矩形的边长…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example: Input: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Output: 4 dp[i][j] = min(dp[i-1][j-1],min(dp[i-1][j],dp[i][j-1]))+1; class Solution { p…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example: Input: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Output: 4 思路是DP, 3种做法, 通用的T: O(m*n) , S: O(m*n) 和只针对部分情况可以use 滚动数组来reduce space成为O(n).A…

在一个由 0 和 1 组成的二维矩阵内,找到只包含 1 的最大正方形,并返回其面积. 示例: 输入: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 输出: 4 方法一:暴力(肯定超时) 方法二: dp, 可以把dp[i][j]表示到i,j为止的正方形边长大小. 到i ,j的正方形大小是min(dp[i - 1][j], min(dp[i][j - 1], dp[i - 1][j - 1])) + 1.最小的那个就是正方形的最大边长大小 class Solutio…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example: Input: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Output: 4 class Solution { public int maximalSquare(char[][] matrix) { if (matrix == nu…

称号: Maximal Square Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. 分析: 利用动态规划求解.建立一个类node.node中成员变量le…

1. Maximal Square 题目链接 题目要求: Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: Return 4. 在GeeksforGeeks有一个解决该问题的方法: 1) Construct a sum matrix S[R…

bzoj1661[Usaco2006 Nov]Big Square 巨大正方形 题意: n*n的图中有一些J点,一些B点和一些空白点,问在空白点添加一个J点所能得到的有4个J点组成最大正方形面积.n≤100. 题解: 枚举两个点,然后根据这两个点组成的边尝试在4个上下两个方向组成四边形. 代码: #include <cstdio> #include <cstring> #include <algorithm> #include <queue> #define…

题目描述 在一个由 0 和 1 组成的二维矩阵内,找到只包含 1 的最大正方形,并返回其面积. 示例: 输入: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 输出: 4 解题思路 动态规划思想,从左上依次遍历到右下,记录以当前位置为右下角顶点的最大正方形的边长,对每个位置作如下操作: 若该位置为0,直接跳过 若该位置为1,则分为两种情况: 若其为左边界或上边界,则更新最大边长为当前数字: 否则检查其紧邻左方.紧邻上方和左上角对应的数字,取他们的最小值再加1即为以…

题目: Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. 题目链接:https://leetcode.com/problems/maximal-square…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example: Input: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Output: 4 在一个由 0 和 1 组成的二维矩阵内,找到只包含 1 的最大正方形,并返回其面积. 示例: 输入: 1 0 1 0 0 1 0 1 1 1 1 1 1…

［抄题］: 在一个二维01矩阵中找到全为1的最大正方形 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 返回 4 [暴力解法]: 时间分析: 空间分析:i j 中保留一排,用指针数组来优化空间存储 ［思维问题］: ［一句话思路］: 棋盘类dp也是用扩展,不过是从右下角开始扩展 最大扩展中的最小值,没见过 ［输入量］:空: 正常情况:特大:特小:程序里处理到的特殊情况:异常情况(不合法不合理的输入): ［画图］: ［一刷］: 第0列初始化完成时,j 从1 开始.第一…

Level   Medium 题目描述: Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. Example: Input: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 Output: 4 思路分析:   动态规划思想,要找到最大的正方形,我们以dp[ i ] [ j ]表示,以第i行…

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: Return 4. 思路: DP,到达当前(非0)结点的最长边长square[i][j] = min(square[i-1][j-1], min(square[i-1][j], square…

2018-09-13 19:19:44 问题描述: 问题求解: 方法一: 使用动态规划来求解,算法时间复杂度O(n^2). dp[i][j] : 以(i, j)为右下角的面积最大的正方形的边长. 初始条件:最上面一行,最左边一列,可以直接得到dp值. 更新公式:matrix[i][j] == '0' - > dp[i][j] = 0    matrix[i][j] == '1' - > dp[i][j] = min(dp[i - 1][j], dp[i - 1][j - 1], dp[i][j…

原题链接在这里:https://leetcode.com/problems/maximal-square/ 这是一道DP题,存储历史信息是到当前点能有的最大square, 用二维数组dp存储. 更新方式是若当前点为0,则不更新,若当前点为1,则取上dp[i-1][j], 左dp[i][j-1], 左上dp[i-1][j-1]的中的最小值,开根号加一,最后平方为dp[i][j]. 初始第一行和第一列,为'1'的时候填成1. Note: 1. 给的matrix数组是char, 所以比较时是根char…