Pick-up sticks--poj2653(判断两线段是否相交)

You can Solve a Geometry Problem too（判断两线段是否相交）

You can Solve a Geometry Problem too Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 199 Accepted Submission(s): 132 Problem Description Many geometry(几何)problems were designed in the ACM/…

Pick-up sticks--poj2653(判断两线段是否相交)

http://poj.org/problem?id=2653 题目大意:有n根各种长度的棍一同洒在地上求在最上面的棍子有那几个分析: 我刚开始想倒着遍历因为n是100000 想着会超时吧后来一看说在上面的不会超过1000个这就放心了简单优化一下就过了最后一个肯定是在最上面的让后从他的下一个开始每一个跟他相交的都是在他下面的下一次就直接不循环他了但是一直wa 彻底懵逼了后来看了学长博客他是正这循环只要有跟他相交的就跳出然后我就正这便利…

NYOJ 1016 判断两线段是否相交

#include<cstdio> #include<cmath> #include<iostream> #include<algorithm> #include<vector> #include<stack> #include<cstring> #include<queue> #include<set> #include<string> #include<map> #incl…

You can Solve a Geometry Problem too （hdu1086）几何，判断两线段相交

You can Solve a Geometry Problem too Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 6837 Accepted Submission(s): 3303 Problem Description Many geometry(几何)problems were designed in the ACM/ICPC. A…

hdu 1086:You can Solve a Geometry Problem too（计算几何，判断两线段相交，水题）

You can Solve a Geometry Problem too Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 6425 Accepted Submission(s): 3099 Problem Description Many geometry(几何)problems were designed in the ACM/I…

hdu 1147:Pick-up sticks（基本题，判断两线段相交）

Pick-up sticks Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 1872 Accepted Submission(s): 706 Problem Description Stan has n sticks of various length. He throws them one at a time on the fl…

poj 1127:Jack Straws（判断两线段相交 + 并查集）

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…

UVALive7461 - Separating Pebbles 判断两个凸包相交

//UVALive7461 - Separating Pebbles 判断两个凸包相交 #include <bits/stdc++.h> using namespace std; #define LL long long typedef pair<int,int> pii; const int inf = 0x3f3f3f3f; ; #define clc(a,b) memset(a,b,sizeof(a)) ; ; void fre() {freopen("in.txt…

如何判断单链表是否存在环 & 判断两链表是否相交

给定一个单链表,只给出头指针h: 1.如何判断是否存在环? 2.如何知道环的长度? 3.如何找出环的连接点在哪里? 4.带环链表的长度是多少? 解法: 1.对于问题1,使用追赶的方法,设定两个指针slow.fast,从头指针开始,每次分别前进1步.2步.如存在环,则两者相遇:如不存在环,fast遇到NULL退出. 2.对于问题2,记录下问题1的碰撞点p,slow.fast从该点开始,再次碰撞所走过的操作数就是环的长度s. 3.问题3:有定理:碰撞点p到连接点的距离=头指针到连接点的距离,因此,分…

poj 1127 -- Jack Straws（计算几何判断两线段相交 + 并查集）

Jack Straws 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 without disturbing the other straws. Here, we are only concerned with if various pairs of straws are…

Pick-up sticks（判断两条线段是否相交）

Time Limit: 3000MS Memory Limit: 65536K Total Submissions: 8351 Accepted: 3068 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, th…

HDU 1147 /// 判断两线段相交

题目大意: 给定n条线段的端点依次放上n条线段判断最后在最上面(不被覆盖)的线段有哪些到当前线段后直接与之前保存的未被覆盖的线段判断是否相交就可以了 #include <cstdio> #include <algorithm> #include <string.h> #include <set> #include <cmath> #define INF 0x3f3f3f3f using namespace std; ; double ad…

TOJ1840: Jack Straws 判断两线段相交+并查集

1840: Jack Straws Time Limit(Common/Java):1000MS/10000MS Memory Limit:65536KByteTotal Submit: 154 Accepted:119 Description In the game of Jack Straws, a number of plastic or wooden "straws" are dumped on the table and players try…

POJ_1227 Jack Straws 【二维平面判两线段相交】

一题面 POJ1127 二分析在平面几何中,判断两线段相交的方法一般是使用跨立实验.但是这题考虑了非严格相交,即如何两个线段刚好端点相交则也是相交的,所以还需要使用快速排斥实验. 这里参考并引用了TangMoon 博客. 1.快速排斥实验由于两个点作为矩形的两个斜对角线端点可以确定一个矩形,则根据两个点确定一个向量,两个向量显然可以确定两个矩形. 对于快速排斥实验,也可尝试逆向思维,如果判断让两个向量确定的两个矩形是否相交部分,相当于判断两个矩形没有相交部分的反. 具体条件就是a.其中一…

HDU 1086 You can Solve a Geometry Problem too（判断线段是否相交水题）

链接:传送门题意:给出 n 个线段找到交点个数思路:数据量小,直接暴力判断所有线段是否相交 /************************************************************************* > File Name: hdu1086.cpp > Author: WArobot > Blog: http://www.cnblogs.com/WArobot/ > Created Time: 2017年05月07日星期日 23时34…

Jack Straws（poj 1127）两直线是否相交模板

http://poj.org/problem?id=1127 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 without disturbing the other straws. Here, we are only concerned wi…

POJ1912 A highway and the seven dwarfs (判断凸包与直线相交 logn)

POJ1912 给定n个点和若干条直线,判断对于一条直线,是否存在两个点在直线的两侧. 显然原命题等价于凸包与直线是否相交. O(n)的算法是显而易见的但是直线数量太多就会复杂到O(n^2)由于n<=100000 会TLE 凸包有个很好的性质,我们没有利用, 那就是凸包的边相对于要判断的直线是极角有序的! 于是得到算法: 构造好凸包后,二分找凸包上第一个与正向直线夹角大于0的线段和第一个与反向直线夹角大于0的线段然后判断两线段的起点是否在直线两侧即可. 代码实现有一点注意的细节:不要用…

ACM1558两线段相交判断和并查集

Segment set Problem Description A segment and all segments which are connected with it compose a segment set. The size of a segment set is the number of segments in it. The problem is to find the size of some segment set. Input In the first line th…

codeForce-589D Boulevard（判断线段是否相交）

题目大意:n个人.一个区间.每个人都会在某个时间段内按相同的速度(所有人的速度都一样,都是1或-1)在他的区间内从一个端点走到另一个端点(只走一次).问每个人会与几个人碰面. 题目分析:将时间看成一个维度,区间位置看成另一个维度.那么每个人的状态便构成了一条二维线段.只需判断有几条线段与该线段相交. 判断两平面线段是否相交: 设线段1的两端点分别为A.B,线段2的两端点分别为C.D. 当两条线段平行时,只需要判断点C或点D是否在线段AB上即可.点C在线段AB上的判断:先判断向量CA与向量CB是否…

2015南阳CCPC D - Pick The Sticks dp

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…

Jack Straws（判断线段是否相交 + 并查集）

/** http://acm.tzc.edu.cn/acmhome/problemdetail.do?&method=showdetail&id=1840 题意: 判断线段是否相交 (包括间接相交) 输入: N(代表有n条线段) sx sy ex ey(一条直线的两端点的坐标) : : : a b(判断第a条和第b条线段是否相交) : : : 0 0输入0 0 询问结束输出…

POJ 3304 Segments（判断直线与线段是否相交）

题目传送门:POJ 3304 Segments 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. Inp…