题意:给你四个点,判断能否先依次通过A,B两点,然后再在某个地方只进行一次直角转弯再一次经过C,D两点: #include <iostream> #include <cstdio> #include <cmath> #include <cstring> #include <algorithm> using namespace std; typedef long long ll; const double eps=1e-12; struct Poi…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1147 思路:判断每条线段,如果将要输入的线段和已经有的线段相交,则这条线段不算. 参考文章:https://blog.csdn.net/hexianhao/article/details/51254487 判断两条线段是否相交:https://www.cnblogs.com/wuwangchuxin0924/p/6218494.html #include<iostream> #include<…

题解:每放一根棍子,都判断一下它与它前面的且在顶端的棍子是否相交,相交的话则将相应的棍子从解空间中除去. #include <cstdio> const double eps=1e-14; const int maxn=1e5+10; struct node{double x1,y1,x2,y2;int w;}e[maxn],f[maxn]; double cross(double x1,double y1,double x2,double y2){return x1*y2-x2*y1;} i…

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…

Pick-up sticks Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 2673    Accepted Submission(s): 975 Problem Description Stan has n sticks of various length. He throws them one at a time on the fl…

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…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1086 判断两条线段是否有交点,我用的是跨立实验法: 两条线段分别是A1到B1,A2到B2,很显然,如果这两条线段有交点,那么可以肯定的是: A1-B1,A2-B1这两个向量分别在B2-B1的两边,判断是不是在两边可以用向量的叉积来判断,这里就不说了,同理B1-A1,B2-A1在A2-A1的两边,当同时满足这两个条件时,说明这两条线段是有交点的. #include<cstdio> #include&…

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…

[题目概述] On an infinite smooth table, there's a big round fixed cylinder and a little ball whose volume can be ignored. Currently the ball stands still at point A, then we'll give it an initial speed and a direction. If the ball hits the cylinder, it w…

Rectangles    HDOJ(2056) http://acm.hdu.edu.cn/showproblem.php?pid=2056 题目描述:给2条线段,分别构成2个矩形,求2个矩形相交面积. 算法:先用快速排斥判断2个矩形是否相交.若不相交,面积为0.若相交,将x坐标排序去中间2个值之差,y坐标也一样.最后将2个差相乘得到最后结果. 这题是我大一的时候做过的,当时一看觉得很水,写起来发现其实没我想的那么水.分了好几类情况没做出来.今天看了点关于判断线段相交的知识,想起了这题便拿来练…