POJ2352:Stars——题解】的更多相关文章

http://poj.org/problem?id=2352 Astronomers晚上仰望星空,看到了很多星星.回到办公桌,Astronomers将这些星星画到二维坐标系,每个星星的坐标都是整数.例如5个星星,坐标分别为(1,1), (5,1), (7,1), (3,3), (5,5): Astronomers想对这些星星定等级,规则是这样的:每个星星左下角有几个星星,它就算几级(包含左边和下面).上面的例子,第1颗星星的等级为0,等2颗星星的等级为1,第3颗星星的等级为2,第4颗星星的等级为…
Stars Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 39186 Accepted: 17027 Description Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star b…
Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher and not to the right of the given star. Astronomers wa…
emm,ssy说可以直接CDQ分治...%%%但是注意到y是有序的,所以可以直接求一下前缀和就行了. 题干: Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher…
题意:输入一n颗星星的x,y坐标,给定判断level的标准,即某颗星星左下边(不高于它,不超过他,相当于以他为基准的第三象限)星星的数目为level, 输出level从0到n的星星个数. //poj2352 #include <iostream> #include <string> #include <cstring> #include <queue> #include <vector> #include <cstdio> using…
https://vjudge.net/problem/POJ-2352 分析: 由于是按照y坐标的升序,y坐标向等的按x的升序的顺序给出星星.那么某个星星的等级数就是在他前面x坐标小于等于他的x坐标的星星的个数. 暴力的时间复杂度为n^2,超时 所以我们要记录前面所有x坐标出现的次数.然后要求出[0,xi]出现的和. 这就是静态二叉检索树 的标准问题了. #include <iostream> #include <cstdio> #include <cstring> #…
http://poj.org/problem?id=2352 #include <cstdio> #include <cstring> #define maxn 400000 using namespace std; int c[maxn],leve[maxn],a,b,n; int lowbit(int x) { )); } void add(int x,int m) { while(x<=maxn) { c[x]+=m; x+=lowbit(x); } } int sum…
经典问题:二维偏序.给定平面中的n个点,求每个点左下方的点的个数. 因为 所有点已经以y为第一关键字,x为第二关键字排好序,所以我们按读入顺序处理,仅仅需要计算x坐标小于<=某个点的点有多少个就行. 这就是所说的:n维偏序,一维排序,二维树状数组,三维 分治 Or 树状数组套平衡树…… <法一>树状数组. #include<cstdio> #include<algorithm> #include<iostream> using namespace st…
传送门 先按照下标x排序,然后依次把y加入树状数组,边加入边统计即可. 注意下标re从零开始,需+1s ——代码 # include <iostream> # include <cstdio> # include <cstring> # include <string> # include <cmath> # include <vector> # include <map> # include <queue>…
2019-05-20 22:52:07 加油,坚持,加油,坚持 !!! #include<iostream> #include<cstdio> #include<cstring> using namespace std; ; int c[MAXN],level[MAXN],n; int lowbit(int x){return x & (-x);} // 求前n项的和 int sum(int n){ ; ){ sum += c[n]; n -= lowbit(n…
每日一题 day7 打卡 Analysis 树状数组 由于题目中给的数据是按y轴排序,我们只需构建x轴的树状数组,也就是说我们只需统计星星i之前一共有多少个x坐标小于或等于Xi的星星,这个数值也就是星星i的等级 又因为树状数组无法处理下标为0的元素(会死循环),所以要把每个x坐标+1 #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define maxn 1…
题目 Stars Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 34016   Accepted: 14839 Description Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a…
[题解]CF997C Sky Full of Stars 为什么我的容斥原理入门题是这道题????????? \(Part-1\)正向考虑 直接考虑不合法合法的方案吧 所以我们设行有\(i\),列有\(j\)有是不同的颜色 所以分这几种情况讨论: \[ i\not=0,j\not=0 \\ i=j=0 \\ ij=0,i+j\not=0 \] 考虑到\(i=j=0​\)对答案没有贡献,所以我们考虑第一式和第三式吧 第三式简单一点,情况就是这样的: 方案数还是比较显然的(我说显然是因为是可以通过我…
Fleeting time does not blur my memory of you. Can it really be 4 years since I first saw you? I still remember, vividly, on the beautiful Zhuhai Campus, 4 years ago, from the moment I saw you smile, as you were walking out of the classroom and turned…
Description Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher and not to the right of the given star. As…
Language:Default Stars Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 52268 Accepted: 22486 Description Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the…
Problem Description Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher and not to the right of the given…
Stars in Your Window   Description Fleeting time does not blur my memory of you. Can it really be 4 years since I first saw you? I still remember, vividly, on the beautiful Zhuhai Campus, 4 years ago, from the moment I saw you smile, as you were walk…
YJC counts stars Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5277 Description YJC是个老火车小司机.一个晚上,他仰望天空,星辰璀璨,他突然觉得,天空就像一个平面,而每一个星辰,就是平面中的一个点.他把这些点编号为1到n.这些点满足任意三点不共线.他把一些点用线段连起来了,但是任意两条线段不会在端点以外相交.如果一个点的集合中任意两个…
Dancing Stars on Me Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5533 Description The sky was brushed clean by the wind and the stars were cold in a black sky. What a wonderful night. You observed that, somet…
题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5533 Dancing Stars on Me Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 601    Accepted Submission(s): 320 Problem Description The sky was brush…
Stars Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 6581    Accepted Submission(s): 2625 Problem Description Astronomers often examine star maps where stars are represented by points on a plan…
Stars Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 6676    Accepted Submission(s): 2659 Problem Description Astronomers often examine star maps where stars are represented by points on a plan…
Dancing Stars on Me Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others) Total Submission(s): 592    Accepted Submission(s): 315 Problem Description The sky was brushed clean by the wind and the stars were cold in a b…
Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher and not to the right of the given star. Astronomers wa…
http://acm.hdu.edu.cn/showproblem.php?pid=1541 Stars Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 5993    Accepted Submission(s): 2384 Problem Description Astronomers often examine star maps…
Connections in Galaxy War In order to strengthen the defense ability, many stars in galaxy allied together and built many bidirectional tunnels to exchange messages. However, when the Galaxy War began, some tunnels were destroyed by the monsters from…
C - Sky Full of Stars 思路: 容斥原理 题解:http://codeforces.com/blog/entry/60357 注意当i > 1 且 j > 1,是同一种颜色 代码: #include<iostream> #include<cstdio> #include<queue> #include<deque> #include<set> #include<cstring> using namesp…
初期:一.基本算法: (1)枚举. (poj1753,poj2965) poj1753 话说我用高斯消元过了这题... poj2965 巧了,用高斯消元01矩阵更快(l o l). (2)贪心(poj1328,poj2109,poj2586)(completed) poj1328 题目可以转化为将以每个岛屿为圆心,半径为d的原与x轴的交点构成的共n个区间,分成尽可能少的块,每个块中的区间有个交集(公共区间至少为一个点).那这就是经典的贪心了. poj2109 这似乎用二分+高精就过了好吧...…
[POJ2482]Stars in Your Window 题面 vjudge 题解 第一眼还真没发现这题居然™是个扫描线 令点的坐标为\((x,y)\)权值为\(c\),则 若这个点能对结果有\(c\)的贡献,必须要矩形左下角的点的范围必须在\(([x,x+w),[y,y+h))\)之间 则按扫描线套路将一个类似矩形的范围拆成线\((x,y1,y2,c)\).\((x+w,y1,y2,-c)\)(依次表示横坐标.下端点纵坐标.上端点纵坐标.权值)即可 最后注意排序时不但要按\(x\)排,也要按…