之前切了道求解最大正方形的题,题解猛戳 这里.这道题 Maximal Rectangle 题意与之类似,但是解法完全不一样. 先来看这道题 Largest Rectangle in Histogram,如果暴力求解,可以枚举每个点为最小值,向两边扩展,复杂度 O(n^2).我们可以维护一个栈,从而将复杂度降低到 O(n),这个栈的思维非常巧妙,参考了 discuss,我是完全想不出来(或者说忘记了).具体代码可以猛戳 这里. 2016-08-07 补:stack 数组维护的是一个单调递增的数组,…

Maximal Rectangle Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area.     使用dpHeight[]数组来记录到第i行为止,第j个位置垂直连续包含多少个1(包括matrxi[i][j]).如: 1 0 1 1 0 1 1 0 1 0 0 1 1 1 1 有如下结果: 第1行: dpHeight[…

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing only 1's and return its area. Example: Input: [ ["1","0","1","0","0"], ["1","0","1",&qu…

链接: https://leetcode.com/problems/maximal-rectangle/ [描述] Given a 2D binary matrix filled with '0's and '1's, find the largest rectangle containing all ones and return its area. [中文描述] 给一个二维数组, 算出里面最大的全1矩形面积,比如: [ ['1','1','1','0'], ['1','1','1','1']…

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 找到01矩形中最大的全1子矩阵. 我自己的思路: 我先用一个跟输入相同大小的矩阵numInCol 存储从当前位置开始向下有多少连续的1. 如 其numInCol 是 然后用一个变量tmpans来记录以某个位置开始,其右下矩形的最大全1矩阵的大小. 方法是如果当前位…

Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram. Above is a histogram where width of each bar is 1, given height = [2,1,5,6,2,3]. The largest…

给定一个只含0和1的数组,求含1的最大矩形面积. Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 这样的题一般看来都是有O(n*m)的解法的. 借助上一题Largest Rectangle in Histogram 的解法. 我们现在把矩阵的每一行当做是上一题的问题,然后遍历所有的行数,取最大数就是解. 这里的…

Find the total area covered by two rectilinear rectangles in a 2D plane. Each rectangle is defined by its bottom left corner and top right corner as shown in the figure. Assume that the total area is never beyond the maximum possible value of int. 对于…

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 解题思路: 求01矩阵中,全是1的子矩阵的最大面积. 把矩阵按照每一行看做是直方图,可以转化为上一题,JAVA实现如下: static public int maximalRectangle(char[][] matrix) { if(matrix.length=…

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 思路:此题的意思是给一个为0或1的矩阵,求所有为1组成的最大矩阵的面积. 此题能够巧妙转化为求最大直方图面积的问题. public class Solution { //其思想是将每一列的1逐行相加,遇0为0.遇1相加 //然后转化为求每一行的最大直方图面积的求解…

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…

Maximal RectangleGiven a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. Show TagsHave you met this question in a real interview? Yes  NoDiscussSOLUTION 1: public class Solution { public i…

作者:jostree 转载请注明出处 http://www.cnblogs.com/jostree/p/4052721.html 题目链接:leetcode Maximal Rectangle 单调栈 该题目是  leetcode Largest Rectangle in Histogram 的二维版本,首先进行预处理,把一个n×m的矩阵化为n个直方图,然后在每个直方图中计算使用单调栈的方法计算面积最大的矩形,然后求得最大的矩形面积即可. Ps:这题直接在网页里面敲完居然1A,不错. 代码如下:…

leetcode面试准备: Maximal Rectangle 1 题目 Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 接口: int maximalRectangle(char[][] matrix) 2 思路 这是一道非常综合的题目,要求在0-1矩阵中找出面积最大的全1矩阵.刚看到这道题会比较无从下手,b…

Largest Rectangle in Histogram Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram. Above is a histogram where width of each bar is 1, given heigh…

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…

Maximal Rectangle Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 如果用DP来做,判断(begin1,end1)~(begin2,end2)范围是否全1,会超时. 对于矩阵matrix,逐行构建height数组,调用Largest Rectangle in Histogram即可. 对matr…

84题和85五题 基本是一样的,先说84题 84--柱状图中最大的矩形( Largest Rectangle in Histogram) 思路很简单,通过循环,分别判断第 i 个柱子能够延展的长度len,最后把len*heights[i] 就是延展开的面积,最后做比对,得出最大. public int largestRectangleArea(int[] heights) { int ans=0; for(int i=0;i<heights.length;i++) { int len=1,lef…

Given a rows x cols binary matrix filled with 0's and 1's, find the largest rectangle containing only 1's and return its area. Example 1: Input: matrix = [["1","0","1","0","0"],["1","0"…

博客搬至blog.csgrandeur.com,cnblogs不再更新. 新的题解会更新在新博客:http://blog.csgrandeur.com/2014/01/15/LeetCode-OJ-Solution/ ———————————————————————————————————————— ———————————————————————————————————————— LeetCode OJ 题解 LeetCode OJ is a platform for preparing tech…

Valid Palindrome吐槽一下Leetcode上各种不定义标准的输入输出(只是面试时起码能够问一下输入输出格式...),此篇文章不是详细的题解,是自己刷LeetCode的一个笔记吧,尽管没有代码,可是略微难一点的都会标出主要思路,便于以后复习 PS:题目中有"水题"两字的都是一遍AC,没有标注的都说明了问题,顺序依照Leetcode上时间倒序排列,少量题目因为和之前的题目有相关性,因此将其放在一起,比方12题和13题,因此中间可能会"缺少"几道题目,缺少的…

Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram. Above is a histogram where width of each bar is 1, given height = [2,1,5,6,2,3]. The largest…

Given a 2D boolean matrix filled with False and True, find the largest rectangle containing all True and return its area. ExampleGiven a matrix: [ [1, 1, 0, 0, 1], [0, 1, 0, 0, 1], [0, 0, 1, 1, 1], [0, 0, 1, 1, 1], [0, 0, 0, 0, 1]]return 6. LeetCode上…

这两天在做leetcode的题目,最大矩形的题目以前遇到很多次了,一直都是用最笨的方法,扫描每个柱子,变换宽度,计算矩形面积,一直都以为就这样O(n2)的方法了,没有想到居然还有研究出了O(n)的算法,真是对GeeksForGeeks大神膜拜啊. 首先是Largest Rectangle in Histogram这个题目 class Solution { public: int largestRectangleArea(vector<int> &height) { int len=he…

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…

85. Maximal Rectangle Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing only 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 0 0 1 0 Return 6.…

Largest Rectangle in Histogram Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram. Above is a histogram where width of each bar is 1, given heigh…

Problem Link: http://oj.leetcode.com/problems/interleaving-string/ Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. For example, Given: s1 = "aabcc", s2 = "dbbca", When s3 = "aadbbcbcac", return t…

Problem link: http://oj.leetcode.com/problems/reverse-words-in-a-string/ Given an input string, reverse the string word by word. For example, Given s = "the sky is blue", return "blue is sky the". LeetCode OJ supports Python now! The s…

一直没有系统地学习过算法,不过算法确实是需要系统学习的.大二上学期,在导师的建议下开始学习数据结构,零零散散的一学期,有了链表.栈.队列.树.图等的概念.又看了下那几个经典的算法——贪心算法.分治算法.动态规划以及回溯算法.不过,都是知其一不知其二的一知半解.到最后,发现学到了一堆的一知半解,在学校课程开这门课时,却又是不得不再学一遍.学一样东西,又不全心全意地主动去把它学好,到最后只是花费了时间,却没真真学到东西.所以,不求学识有多广,但求所学的都精. 一个偶然的机会,让我在网上找到了一本社区…