题意: 两个凸多面体,可以任意摆放,最多贴着,问他们重心的最短距离. 解法: 由于给出的是凸多面体,先构出两个三维凸包,再求其重心,求重心仿照求三角形重心的方式,然后再求两个多面体的重心到每个多面体的各个面的最短距离,然后最短距离相加即为答案,因为显然贴着最优. 求三角形重心见此: http://www.cnblogs.com/whatbeg/p/4234518.html 代码:(模板借鉴网上模板) #include <iostream> #include <cstdio> #in…

Ultimate Weapon Time Limit: 2000MS   Memory Limit: 131072K Total Submissions: 2074   Accepted: 989 Description In year 2008 of the Cosmic Calendar, the Aliens send a huge armada towards the Earth seeking after conquest. The humans now depend on their…

3D Convex Hull Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1266    Accepted Submission(s): 658 Problem Description There are N points in 3D-space which make up a 3D-Convex hull*. How many f…

http://acm.hdu.edu.cn/showproblem.php?pid=4273 Rescue Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 337    Accepted Submission(s): 243 Problem Description I work at NASA outer space rescue te…

http://acm.hdu.edu.cn/showproblem.php?pid=4266 The Worm in the Apple Time Limit: 50000/20000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 547    Accepted Submission(s): 252 Problem Description Willy the Worm was…

题意:给定n个只有大写字母组成的字符串,选取尽可能多的字符串,使得这些字符串中每个字母的个数都是偶数.n<=24 思路:直接枚举每个字符串的选或不选,复杂度是O(2^n).其实还有更简便的方法. 对于每个字母,其实具体出现了多少次并不重要,重要的是奇数次还是偶数次,我们用0对应奇数次,1对应偶数次.对于每个字符串,我们就可以计算出对应的二进制数,方法如下.如果A出现奇数次,那么二进制数第一个位置为1,偶数次为0:如果B出现奇数次,那么二进制数第二个位置为1,偶数次为0……以此类推,每个位置都有一…

思路: 看到这个题目就发现所需最短时间也就是房子和相遇点的最远距离具有凹凸性,很容易就想到了三分法枚举. 找出所有房子的X坐标的最小最大值作为上下界. 代码如下: #include<stdio.h> #include<math.h> #include<algorithm> #define M 50005 #include<iostream> #define inf 200005 #define eps 1e-8 using namespace std; st…

链接:http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=453 Time Limit: 2 Seconds      Memory Limit: 65536 KB There are a lot of trees in an area. A peasant wants to buy a rope to surround all these trees. So at first he must know the minimal r…

POJ 2251 Dungeon Master /UVA 532 Dungeon Master / ZOJ 1940 Dungeon Master(广度优先搜索) Description You are trapped in a 3D dungeon and need to find the quickest way out! The dungeon is composed of unit cubes which may or may not be filled with rock. It ta…

POJ 1511 Invitation Cards / UVA 721 Invitation Cards / SPOJ Invitation / UVAlive Invitation Cards / SCU 1132 Invitation Cards / ZOJ 2008 Invitation Cards / HDU 1535 (图论,最短路径) Description In the age of television, not many people attend theater perfor…