题目链接:http://acm.timus.ru/problem.aspx?space=1&num=1043 题目大意:一个2000*2000方格坐标,x,y范围都是[-1000,1000].现在给你一个圆弧,告诉你圆弧的两个端点和任意一个中间点.现在要你算出最小的矩形(长和宽都要为整数,即四个顶点在方格顶点上)来完全覆盖这个圆弧. 算法思路:很明显要算出圆心,这个可以有线段中垂线交求,也可以由方程,只是很麻烦.然后以圆心找出这个圆的左右上下四个极点,判断是否在圆弧上(用叉积即可),与给出的三个…

http://poj.org/problem?id=1266 Cover an Arc. Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 823   Accepted: 308 Description A huge dancing-hall was constructed for the Ural State University's 80-th anniversary celebration. The size of t…

2038. Minimum Vertex Cover Time limit: 1.0 secondMemory limit: 64 MB A vertex cover of a graph is a set of vertices such that each edge of the graph is incident to at least one vertex of the set. A minimum vertex cover is a vertex cover with minimal…

题目传送门 /* 题意:最少需要多少条线段能覆盖[0, m]的长度 贪心:首先忽略被其他线段完全覆盖的线段,因为选取更长的更优 接着就是从p=0开始,以p点为标志,选取 (node[i].l <= p && p < node[i+1].l) 详细解释:http://www.cnblogs.com/freezhan/p/3219046.html */ #include <cstdio> #include <iostream> #include <al…

1245. Pictures Time limit: 1.0 secondMemory limit: 64 MB Artist Ivanov (not the famous Ivanov who painted "Christ's apparition to people", but one of the many namesakes) once managed to rent inexpensively an excellent studio. Alas, as he soon di…

链接: http://acm.timus.ru/problem.aspx?space=1&num=1303 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=26733#problem/D D - Minimal Coverage Time Limit:1000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Submit Status Practice UR…

Cops and Thieves Time Limit: 1000ms Memory Limit: 16384KB This problem will be judged on Ural. Original ID: 127764-bit integer IO format: %lld      Java class name: (Any) The Galaxy Police (Galaxpol) found out that a notorious gang of thieves has pla…

Convert BSpline Curve to Arc Spline in OpenCASCADE eryar@163.com Abstract. The paper based on OpenCASCADE algorithms to approximate the NURBS curve to arc spline. The method is most useful in numerical control to drive the cutter along straight line…

1. Exact Cover Problem DLX是用来解决精确覆盖问题行之有效的算法. 在讲解DLX之前,我们先了解一下什么是精确覆盖问题(Exact Cover Problem)? 1.1 Polyomino 多联骨牌(Polyomino)是一种类似于七巧板的棋盘游戏: 如下图所示,除去中间\(4\)个方格不允许放置任何东西,这个棋盘总共有\(8*8-4=60\)个方格 将这\(12\)个由\(5\)个方格组成的图形全部放入到棋盘中,满足每个格子都被使用,而且只被使用一次. 每个格子都被覆…

ARC 全称:Automatic Reference Counting 使用ARC 只需要在建立一个新的项目的时候把 下面的√打上 Xcode5以后都会默认建议开发者使用ARC机制 新的项目中如果有部分文件不想使用ARC就 在Build Phases中找到那个文件 后面修改成-fno-objc-arc 就得项目中如果有部分文件想使用ARC就 Build Phases中找到那个文件 后面修改成-f-objc-arc 在使用了ARC开发程序中不能再出现release或者autorelease 否则就…