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…

// 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…

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…

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…

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: 按顺序扔木棒,求出最上层的木棒是哪些. 解法: 由于最上层的木棒不超过1000个,所以用一个队列存储最上层的木棒,每次扔出一个木棒后,都与队列中的木棒一一判断,看此木棒是否在某一最上层的木棒的上面,即判线段是否相交(两次跨立实验),如果相交,则将那个被压的木棒抛出队列,最后再加入扔的这个木棒到队列中. 代码: #include <iostream> #include <cstdio> #include <cstring> #include <cstdlib…

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…

Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 13377   Accepted: 5039 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…

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…

题目大意:有一个木棒,按照顺序摆放,求出去上面没有被别的木棍压着的木棍.....   分析:可以维护一个队列,如果木棍没有被压着就入队列,如果判断被压着,就让那个压着的出队列,最后把这个木棍放进队列,不过速度并不快,枚举才是最快的......据说是任意时刻没有超过1000个top sticks.....很难注意到.   代码如下: ===================================================================================…

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 is these sticks such that there is no stick on top of them. Stan has noticed…

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…

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)…

题意:给定n个木棍依次放下,要求最终判断没被覆盖的木棍是哪些. 思路:快速排斥以及跨立实验可以判断线段相交. #include<algorithm> #include<cstdio> #include<cmath> #include<cstring> #include<iostream> ; struct Point{ double x,y; Point(){} Point(double x0,double y0):x(x0),y(y0){} }…

计算几何,判断线段相交 注意题目中的一句话:You may assume that there are no more than 1000 top sticks. 我认为是没有描述清楚的,如果不是每次扔完都保证不超过1000,此题很难做吧. 如果每次扔完保证小于1000根在顶部,那么暴力即可. 开一个vector保存每次扔完在顶部的棒子,下一次扔的时候,只要在删除vector中与扔的相交的棒子,然后再把这个棒子压入进来,最后留下的就是答案 #include<cstdio> #include&l…

Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 12861   Accepted: 4847 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…

Pick-up sticks 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 is these sticks such…

http://poj.org/problem?id=2653 Pick-up sticks Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 9531   Accepted: 3517 Description Stan has n sticks of various length. He throws them one at a time on the floor in a random way. After finishi…

一.概念介绍 1. 双端队列 双端队列是一种线性表,是一种特殊的队列,遵守先进先出的原则.双端队列支持以下4种操作: (1)   从队首删除 (2)   从队尾删除 (3)   从队尾插入 (4)   查询线性表中任意一元素的值 2. 单调队列 单调队列是一种特殊的双端队列,其内部元素具有单调性.最大队列与最小队列是两种比较常用的单调队列,其内部元素分别是严格单调递减(不是非递增)和严格单调递增(不是非递减)的. 单调队列的常用操作如下: (1) 插入:若新元素从队尾插入后会破坏单调性,则删除队…

/***************************************************************** 题目: Sliding Window(poj 2823) 链接: http://poj.org/problem?id=2823 题意: 给一个数列,找所有连续k个数的最小值和最大值. 算法: 单调队列(入门) *******************************************************************/ #include<…

Expedition Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 8053   Accepted: 2359 Description A group of cows grabbed a truck and ventured on an expedition deep into the jungle. Being rather poor drivers, the cows unfortunately managed to…

Area Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 5811   Accepted: 2589 Description Being well known for its highly innovative products, Merck would definitely be a good target for industrial espionage. To protect its brand-new resear…

poj 1821 Fence \(solution:\) 这道题因为每一个粉刷的人都有一块"必刷的木板",所以可以预见我们的最终方案里的粉刷匠一定是按其必刷的木板的顺序排列的.这就提示了我们可以用线性 $ DP $,只需要将粉刷匠按必刷的木板排序即可. 设 $F[ $ i $ ][j]$ 表示前 $ i $ 个粉刷匠刷了前 $ j $ 快木板的最大收益(可以有木板不刷!).我们可以根据题意列出转移方程: 首先这个粉刷匠一块木板也不刷 这块木板不刷 这个粉刷匠从第k块木板刷到第 $ j…

我们从最简单的问题开始: 给定一个长度为N的整数数列a(i),i=0,1,...,N-1和窗长度k. 要求: f(i) = max{a(i-k+1),a(i-k+2),..., a(i)},i = 0,1,...,N-1 问题的另一种描述就是用一个长度为k的窗在整数数列上移动,求窗里面所包含的数的最大值. 解法一: 很直观的一种解法,那就是从数列的开头,将窗放上去,然后找到这最开始的k个数的最大值,然后窗最后移一个单元,继续找到k个数中的最大值. 这种方法每求一个f(i),都要进行k-1次的比较…