2018-09-15 10:23:44 一.Largest Rectangle in Histogram 在求解最大的矩形面积之前,我们先讨论一条最大直方图面积的问题. 问题描述: 问题求解: 解法一.朴素解法,O(n ^ 2). 解决的思路就是遍历一遍,如果当前的数比后一个数要小,那么当前的额数字肯定不可能是最大面积的右边界,遍历下一个数: 如果当前数比后一个大,那么假设当前的为右边界,向左进行遍历,计算面积最大值. public int largestRectangleArea(int[]…

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…

We are given a list of (axis-aligned) rectangles.  Each rectangle[i] = [x1, y1, x2, y2] , where (x1, y1) are the coordinates of the bottom-left corner, and (x2, y2) are the coordinates of the top-right corner of the ith rectangle. Find the total area…

223. 矩形面积 223. Rectangle Area 题目描述 在二维平面上计算出两个由直线构成的矩形重叠后形成的总面积. 每个矩形由其左下顶点和右上顶点坐标表示,如图所示. LeetCode223. Rectangle Area中等 示例: 输入: -3, 0, 3, 4, 0, -1, 9, 2 输出: 45 说明: 假设矩形面积不会超出 int 的范围. Java 实现 class Solution { public int computeArea(int A, int B, int…

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,…

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 此题是之前那道的Largest Rectangle in Histogram 直方图中最大的矩形 的扩展,这道题的二维矩阵每一层向上都可以看做一个直方图,输入矩阵有多少行,就可以形成多少个直方图,对每个直方图都调用Largest Rectangle in Hist…

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…

Find the total area covered by two rectilinear rectangles in a2D 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. Cre…

Largest Rectangle in a Histogram Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 15013    Accepted Submission(s): 4357 Problem Description A histogram is a polygon composed of a sequence of rec…

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. Example: Input: A = -3, B = 0, C = 3, D = 4, E = 0, F = -1, G = 9, H = 2 Output:…