Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 25335    Accepted Submission(s): 6716 Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat…

题意: 给出平面上的n个点,问任意点对之间的最短距离是多少? 思路: 先将所有点按照x坐标排序,用二分法将n个点一分为二个部分,递归下去直到剩下两或一个点.对于一个部分,左右部分的答案分别都知道,那么可能的答案就是min(left_ans,right_ans) .注意更小的点对可能一个在左,一个在右.所以还得处理两个边内的紧靠着的部分,如果左边的一个点到达中线的距离已经超过当前最短距离,那么这个点到达右边任意一个点也不会是最短距离了.同时,若一左一右的两个点的y距离已经超过目前最短距离,那么也不…

传送门: http://acm.hdu.edu.cn/showproblem.php?pid=1007 Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 62916    Accepted Submission(s): 16609 Problem Description Have you ever played…

Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 58566    Accepted Submission(s): 15511 Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat…

Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 29344    Accepted Submission(s): 7688 Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat…

Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 47104    Accepted Submission(s): 12318 Problem Description Have you ever played quoit in a playground? Quoit is a game in which fla…

Quoit Design Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys encircled awarded. In the field of Cyberground, the position of each toy is fixed, and the ri…

http://acm.hdu.edu.cn/showproblem.php?pid=1007 上半年在人人上看到过这个题,当时就知道用分治但是没有仔细想... 今年多校又出了这个...于是学习了一下平面内求最近点对的算法...算导上也给了详细的说明 虽然一看就知道直接用分治O(nlogn)的算法 , 但是平面内最近点对的算法复杂度证明我看了一天也没有完全看明白... 代码我已经做了一些优化...但肯定还能进一步优化..我是2s漂过的非常惭愧...(甚至优化以后时间还多了...不明白原因 /***…

Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys encircled awarded.In the field of Cyberground, the position of each toy is fixed, and the ring is carefull…

大致题意:给N个点,求最近点对的距离 d :输出:r = d/2. // Time 2093 ms; Memory 1812 K #include<iostream> #include<cstdio> #include<cmath> #include<algorithm> #define eps 1e-8 #define maxn 100010 #define sqr(a) ((a)*(a)) using namespace std; int sig(dou…

Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys encircled awarded.In the field of Cyberground, the position of each toy is fixed, and the ring is carefull…

题意:求平面最近点对之间的距离 解:首先可以想到枚举的方法,枚举i,枚举j算点i和点j之间的距离,时间复杂度O(n2). 如果采用分治的思想,如果我们知道左半边点对答案d1,和右半边点的答案d2,如何求跨两边点之间的答案呢?显然只用枚举中线两边d=min(d1,d2)范围的点,并且每个点都只需要枚举上下范围在d以内的点,显然这样的点不会很多. #include <algorithm> #include <iostream> #include <cstring> #inc…

传送门 Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys encircled awarded…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1007 题意:给出n个点求最短的两点间距离除以2. 题解:简单的分治. 其实分治就和二分很像二分的写dfs然后复杂度就是log(n*log(n)*log(n)) #include <iostream> #include <cstring> #include <cstdio> #include <algorithm> #include <cmath> u…

原题地址 题目大意 查询平面内最近点对的距离,输出距离的一半. 暴力做法 枚举每一个点对的距离直接判断,时间复杂度是 $ O(n^2) $,对于这题来说会超时. 那么我们考虑去优化这一个过程,我们在求距离的过程中其实有很多的计算是没有必要的,比如已经有一个暂时的最小值 $ d \(,如果有\) dis>d $,那么这个 $ dis $是没有贡献的,那么我们怎么除去这些不必要的答案呢? 我们可以考虑分治,假设已经求出了两个小区间 $ A , B $的最小值,那么合并的大区间 $ C $ 的最小值实…

暂鸽 #include<cstdio> #include<algorithm> #include<cstring> #include<cmath> #define N 100010 using namespace std; void chkmin(double x,double y) {if (x>y) x=y;} int n; struct point { double x,y; point(){}; point(double _x,double _…

Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 29694    Accepted Submission(s): 7788 Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat…

意甲冠军:给n坐标点.半一对点之间的距离所需的距离最近. 分析:分而治之的方法,最近点. #include<iostream> #include<algorithm> #include<cmath> using namespace std; #define N 100005 double min(double a,double b) { return a<b? a:b; } struct POINT { double x,y; }; POINT point[N],…

题目大意:给定平面上的 n 个点,求距离最近的两个点的距离的一半. n <= 10^5.   晕乎乎的度过了一上午... 总之来学习下分治吧233 分治就是把大问题拆成小问题,然后根据对小问题处理出的结果合并成大问题的答案 比如说这道题,如果我们按照X坐标把所有的点分成两组: (木哈哈请叫我盗图狂魔○( ^皿^)っHiahiahia… 像上面我们把点分成了集合S1,S2 点对对应的被划分成3种:S1内,S2内,跨S1.S2 那假若我们分别处理出了S1,S2内的答案,再取个min叫做d 那么跨过分…

题意:有n个点,问其中某一对点的距离最小是多少 分析:分治法解决问题:先按照x坐标排序,求解(left, mid)和(mid+1, right)范围的最小值,然后类似区间合并,分离mid左右的点也求最小值 POJ 3714 #include <cstdio> #include <cstring> #include <cmath> #include <algorithm> const int N = 1e5 + 5; const double INF = 1e…

Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys encircled awarded. In the field of Cyberground, the position of each toy is fixed, and the ring is careful…

题意是求出所给各点中最近点对的距离的一半(背景忽略). 用分治的思想,先根据各点的横坐标进行排序,以中间的点为界,分别求出左边点集的最小距离和右边点集的最小距离,然后开始合并,分别求左右点集中各点与中间点的距离,从这些距离与点集中的最小距离比较,求得最小距离,此处可按纵坐标排序,将纵坐标距离已经大于之前最小距离的部分都剪枝. 代码如下: #include <bits/stdc++.h> using namespace std; ]; struct point { double x,y; }p[…

ZOJ2107 给定10^5个点,求距离最近的点对的距离. O(n^2)的算法是显而易见的. 可以通过分治优化到O(nlogn) 代码很简单 #include<iostream> #include<stdio.h> #include<stdlib.h> #include<string.h> #include<math.h> #include<algorithm> #include<queue> #include<ve…

思路: 分治 套路题 //By SiriusRen #include <cmath> #include <cstdio> #include <algorithm> using namespace std; ; typedef double db; int n; struct P{db x,y;P(){}P(db X,db Y){x=X,y=Y;}}p[N],t[N]; P operator-(P a,P b){return P(a.x-b.x,a.y-b.y);} db…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1007 Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 42865    Accepted Submission(s): 11128 Problem Description Have you ever played…

Quoit Design Time Limit: 10000/5000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 30919 Accepted Submission(s): 8120 Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rings…

Quoit Design Time Limit: 5 Seconds      Memory Limit: 32768 KB Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys encircled awarded. In the field of Cyberground, the position of…

题目链接 Quoit Design Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 29547    Accepted Submission(s): 7741 Problem Description Have you ever played quoit in a playground? Quoit is a game in which…

http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=1107 Quoit Design Time Limit: 5 Seconds      Memory Limit: 32768 KB Have you ever played quoit in a playground? Quoit is a game in which flat rings are pitched at some toys, with all the toys…

主题: Quoit Design Time Limit: 10000/5000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 136 Accepted Submission(s): 77   Problem Description Have you ever played quoit in a playground? Quoit is a game in which flat rin…