一定要注意位运算的优先级!!!我被这个卡了好久 判断线段相交模板题. 叉积,点积,规范相交,非规范相交的简单模板 用了“链表”优化之后还是$O(n^2)$的暴力,可是为什么能过$10^5$的数据? #include<cmath> #include<cstdio> #include<cstring> #include<algorithm> #define N 100005 using namespace std; struct Point { double x…

题目链接:http://poj.org/problem?id=2653 Time Limit: 3000MS Memory Limit: 65536K Description Stan has n sticks of various length. He throws them one at a time on the floor in a random way. After finishing throwing, Stan tries to find the top sticks, that…

判断线段与线段相交 莫名其妙的数据量 #include <iostream> #include <cstdio> #include <vector> #include <cmath> #include <cstring> using namespace std; ; int dcmp(double x) { : (x < ? - : ); } struct Point { double x,y; Point(, ) : x(a), y(b)…

// 线段相交 POJ 2653 // 思路:数据比较水,据说n^2也可以过 // 我是每次枚举线段,和最上面的线段比较 // O(n*m) // #include <bits/stdc++.h> #include <iostream> #include <cstdio> #include <cstdlib> #include <algorithm> #include <vector> #include <math.h>…

Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 11884   Accepted: 4499 Description Stan has n sticks of various length. He throws them one at a time on the floor in a random way. After finishing throwing, Stan tries to fin…

// 线段和矩形相交 POJ 1410 // #include <bits/stdc++.h> #include <iostream> #include <cstdio> #include <cstdlib> #include <algorithm> #include <vector> #include <math.h> using namespace std; #define LL long long typedef p…

// 判断线段和直线相交 POJ 3304 // 思路: // 如果存在一条直线和所有线段相交,那么平移该直线一定可以经过线段上任意两个点,并且和所有线段相交. #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> #include <map> #include <set> #include <queue> #includ…

POJ 2828 Buy Tickets(排队问题,线段树应用) ACM 题目地址:POJ 2828 Buy Tickets 题意:  排队买票时候插队.  给出一些数对,分别代表某个人的想要插入的位置Pos_i和他的Val_i,求出最后的队列的val顺序. 分析:  也是一道非常巧妙的题目.  刚開始天真的以为sort一下即可了.wa了一发后发现我错了...  原来能够非常巧妙的用线段树做.因为某个人想要插入posi位置,插入后他就在posi位置上了,可是可能其它人会插到他前面来,他的位置就会…

Intersecting Lines Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 13605   Accepted: 6049 Description We all know that a pair of distinct points on a plane defines a line and that a pair of lines on a plane will intersect in one of three…

链接: http://poj.org/problem?id=1039 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=22013#problem/B Pipe Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 8350   Accepted: 2501 Description The GX Light Pipeline Company started to prep…

Segments Time Limit: 1000MS   Memory Limit: 65536K       Description Given n segments in the two dimensional space, write a program, which determines if there exists a line such that after projecting these segments on it, all projected segments have…

Jack Straws Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 2911   Accepted: 1322 Description In the game of Jack Straws, a number of plastic or wooden "straws" are dumped on the table and players try to remove them one-by-one witho…

Intersection Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 16322   Accepted: 4213 Description You are to write a program that has to decide whether a given line segment intersects a given rectangle. An example: line: start point: (4,9)…

题目链接 Intersection Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 12040   Accepted: 3125 Description You are to write a program that has to decide whether a given line segment intersects a given rectangle. An example: line: start point:…

Segments Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 10921   Accepted: 3422 Description Given n segments in the two dimensional space, write a program, which determines if there exists a line such that after projecting these segments…

Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 8862   Accepted: 3262 Description Stan has n sticks of various length. He throws them one at a time on the floor in a random way. After finishing throwing, Stan tries to find…

Pick The Sticks Time Limit: 15000/10000 MS (Java/Others)    Memory Limit: 65535/65535 K (Java/Others)Total Submission(s): 593    Accepted Submission(s): 193 Problem Description The story happened long long ago. One day, Cao Cao made a special order c…

题目链接 题意 : 如果两个线段相交就属于同一集合,查询某条线段所属集合有多少线段,输出. 思路 : 先判断与其他线段是否相交,然后合并. #include <cstdio> #include <cstring> #include <iostream> #include <cmath> #define eps 1e-8 #define zero(x) (((x) > 0 ? (x) : (-x)) < eps) using namespace s…

D - Pick The Sticks Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 无 Description The story happened long long ago. One day, Cao Cao made a special order called "Chicken Rib" to his army. No one got his point and all became very panic. However, Cao…

题目大意:给一个凸多边形(点不是按顺序给的),然后计算给出的线段在这个凸多边形里面的长度,如果在边界不计算. 分析:WA2..WA3...WA4..WA11...WA的无话可说,总之细节一定考虑清楚,重合的时候一定是0 代码如下: ========================================================================================================= #include<stdio.h> #include&…

POJ_3304_Segments_线段判断是否相交 Description Given n segments in the two dimensional space, write a program, which determines if there exists a line such that after projecting these segments on it, all projected segments have at least one point in common.…

Problem Description In a galaxy far, far away, there are two integer sequence a and b of length n.b is a static permutation of 1 to n. Initially a is filled with zeroes.There are two kind of operations:1. add l r: add one for al,al+1...ar 2. query l…

Pick The Sticks Time Limit: 15000/10000MS (Java/Others)     Memory Limit: 65535/65535KB (Java/Others) The story happened long long ago. One day, Cao Cao made a special order called "Chicken Rib" to his army. No one got his point and all became v…

D - Pick The Sticks Description The story happened long long ago. One day, Cao Cao made a special order called "Chicken Rib" to his army. No one got his point and all became very panic. However, Cao Cao himself felt very proud of his interesting…

题意:给你n条线段依次放到二维平面上,问最后有哪些没与前面的线段相交,即它是顶上的线段 题解:数据弱,正向纯模拟可过 但是有一个陷阱:如果我们从后面向前枚举,找与前面哪些相交,再删除前面那些相交的线段,这样就错了 因为如果线段8与5,6,7相交了,我们接下来不能直接判断4,我们还要找7,6,5与之前哪些相交 #include<set> #include<map> #include<queue> #include<stack> #include<cmat…

题意:n根木棍随意摆放在一个平面上,问放在最上面的木棍是哪些. 思路:线段相交,因为题目说最多有1000根在最上面.所以从后往前处理,直到木棍没了或者最上面的木棍的总数大于1000. #include<stdio.h> #include<string.h> #include<math.h> #include<iostream> using namespace std; ; ; int sgn(double x){ ; ) ; ; } struct point…

题目传送门 题意:就是小时候玩的一种游戏,问有多少线段盖在最上面 分析:简单线段相交,队列维护当前最上的线段 /************************************************ * Author :Running_Time * Created Time :2015/10/26 星期一 15:37:36 * File Name :POJ_2653.cpp ************************************************/ #inclu…

题目链接 题意 : 把每根棍往地上扔,找出最后在上面的棍,也就是说找出所有的没有别的棍子压在它的上面的棍子. 思路 : 对于每根棍子,压在他上面的棍子一定是在它之后扔的棍子,所以在找的时候只要找它之后的线段是否与他相交即可. #include <stdio.h> #include <iostream> #include <math.h> #include <string.h> using namespace std ; struct point { doub…

Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 7699   Accepted: 2843 Description Stan has n sticks of various length. He throws them one at a time on the floor in a random way. After finishing throwing, Stan tries to find…

Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 10330   Accepted: 3833 Description Stan has n sticks of various length. He throws them one at a time on the floor in a random way. After finishing throwing, Stan tries to fin…