An Easy Physics Problem Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 3845    Accepted Submission(s): 768 Problem Description On an infinite smooth table, there's a big round fixed cylinder an…

HDU 5572 An Easy Physics Problem (计算几何) 题目链接http://acm.hdu.edu.cn/showproblem.php?pid=5572 Description 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 p…

An Easy Physics Problem Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 1430    Accepted Submission(s): 270 Problem Description On an infinite smooth table, there's a big round fixed cylinder an…

[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…

2015上海区域赛现场赛第5题. 题目连接:http://acm.hdu.edu.cn/showproblem.php?pid=5572 题意:在平面上,已知圆(O, R),点B.A(均在圆外),向量V. 一个小球从A出发,沿速度向量V匀速前进,若撞到圆则发生弹性碰撞,沿“反射方向”继续匀速前进.问A点能否经过B点. 题目读懂了,把所有情况都考虑全,流程图就出来了,然后直接套模版即可(注意有些功能可剪裁~) 我的第一道计算几何,WA了一个星期啊...原因有姿势不对,精度不对,还有输出不对的. 不…

计算几何的题做的真是少之又少. 之前wa以为是精度问题,后来发现是情况没有考虑全... 题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=5572 题意: 给定起点A和方向V,路径中遇到圆柱体会发生折射,问能否到达终点B. 分析: 将路径表示为a+t∗v得到关于t的二元方程组,求出Δ. Δ小于等于0时,表示不会发生折射.直接判断ab是否共线. Δ大于0时,求出根. 根小于0说明路上不会发生折射,判断ab是否共线. 根大于等于0,仍然要判断ab是否共线…

题目链接:HDU 5572 Problem Description 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 t…

题意: 光滑平面,一个刚性小球,一个固定的刚性圆柱体 ,给定圆柱体圆心坐标,半径 ,小球起点坐标,起始运动方向(向量) ,终点坐标 ,问能否到达终点,小球运动中如果碰到圆柱体会反射. 学到了向量模板,写法简洁. #include<cstdio> #include<cstring> #include<algorithm> #include<iostream> #define clc(a,b) sizeof(a,b,sizeof(a)) #define LL l…

HDU 4974 A simple water problem pid=4974" target="_blank" style="">题目链接 签到题,非常easy贪心得到答案是(sum + 1) / 2和ai最大值的最大值 代码: #include <cstdio> #include <cstring> #include <algorithm> using namespace std; const int N =…

As Easy As A+B Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 53368    Accepted Submission(s): 22939 Problem Description These days, I am thinking about a question, how can I get a problem as…

As Easy As A+B Problem Description These days, I am thinking about a question, how can I get a problem as easy as A+B? It is fairly difficulty to do such a thing. Of course, I got it after many waking nights.Give you some integers, your task is to so…

HDU 3861 The King's Problem 题目链接 题意:给定一个有向图,求最少划分成几个部分满足以下条件 互相可达的点必须分到一个集合 一个对点(u, v)必须至少有u可达v或者v可达u 一个点仅仅能分到一个集合 思路:先强连通缩点,然后二分图匹配求最小路径覆盖 代码: #include <cstdio> #include <cstring> #include <vector> #include <algorithm> #include &l…

今天去老校区找她,不想带电脑了,所以没时间A题了 /*******************************************************************/ As Easy As A+B Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 45926    Accepted Submission(s): 196…

As Easy As A+B Problem Description These days, I am thinking about a question, how can I get a problem as easy as A+B? It is fairly difficulty to do such a thing. Of course, I got it after many waking nights. Give you some integers, your task is to s…

http://acm.hdu.edu.cn/game/entry/problem/list.php?chapterid=1§ionid=2 1.2.5 #include<stdio.h> /* 题意:找闰年. if((i%4==0 && i%100!=0) || i%400==0)count++; 3 2005 25 1855 12 2004 10000 2108 1904 43236 */ int main() { int t,y,n; int i,count=0; whil…

http://acm.hdu.edu.cn/showproblem.php?pid=5475 An easy problem Time Limit: 8000/5000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 755 Accepted Submission(s): 431 Problem Description One day, a useless calculator was…

An easy problem Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5475 Description One day, a useless calculator was being built by Kuros. Let's assume that number X is showed on the screen of calculator. At first,…

An Easy Problem for Elfness Time Limit: 5000/2500 MS (Java/Others)    Memory Limit: 65535/65535 K (Java/Others)Total Submission(s): 1148    Accepted Submission(s): 234 Problem Description Pfctgeorge is totally a tall rich and handsome guy. He plans t…

http://acm.hdu.edu.cn/showproblem.php?pid=2132 Problem Description We once did a lot of recursional problem . I think some of them is easy for you and some if hard for you.Now there is a very easy problem . I think you can AC it.  We can define sum(n…

Problem Description We once did a lot of recursional problem . I think some of them is easy for you and some if hard for you. Now there is a very easy problem . I think you can AC it. We can define sum(n) as follow: if i can be divided exactly by 3 s…

问题: 開始尝试用字符做数组元素.可是并没实用. 在推断语句时把a z排出了. An easy problem Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 16516    Accepted Submission(s): 11096 Problem Description we define f(A) = 1, f(a) = -1,…

http://acm.hdu.edu.cn/showproblem.php?pid=2123 Problem Description In this problem you need to make a multiply table of N * N ,just like the sample out. The element in the ith row and jth column should be the product(乘积) of i and j.   Input The first…

Problem Description In this problem you need to make a multiply table of N * N ,just like the sample out. The element in the ith row and jth column should be the product(乘积) of i and j. Input The first line of input is an integer C which indicate the…

转载请注明出处,谢谢http://blog.csdn.net/ACM_cxlove?viewmode=contents    by---cxlove 题意:给出一个带边权的图.对于每一个询问(S , T , K , A , B),有两种操作,加一条单位边花费为A,将某条边流量扩展一个单位花费为B,在预算为K的情况下求S到T最大流的最大值. http://acm.hdu.edu.cn/showproblem.php?pid=4729 做法:如果A <= B,很明显只做添加边操作,而且只加在S -…

http://acm.hdu.edu.cn/showproblem.php?pid=3521 题意 对于矩阵A,求e^A的值. 分析 这个定眼一看好像很熟悉,就是泰勒展开,可惜自己的高数已经还给老师了...比赛时不敢直接暴力写,实际上循环到一定次数,余式对结果的影响就相当小了.循环到50几次就可以了 #include<iostream> #include<cmath> #include<cstring> #include<queue> #include<…

Problem Description Pfctgeorge is totally a tall rich and handsome guy. He plans to build a huge water transmission network that covers the whole southwest China. To save the fund, there will be exactly one path between two cities. Since the water ev…

题意 链接:https://cn.vjudge.net/problem/HDU-4729 给你n个点,然你求两个点s和t之间的最大流.而且你有一定的钱k,可以进行两种操作 1.在任意连个点之间建立一个单位1的流,费用a 2.将原先的流扩大1个单位,费用b 思路 题目已经说了是一棵树,那么树上两点的最大流就是两点路径上的最小值.其实两种操作各一次对最大流的贡献是相等的.我们分类讨论: 如果a<=b,直接算第一种方案即可,直接给s.t连一条边,对答案的贡献是k/a. 如果a>b,分两种情况.如果k…

Problem Description When Teddy was a child , he was always thinking about some simple math problems ,such as "What it's 1 cup of water plus 1 pile of dough .." , "100 yuan buy 100 pig" .etc.. One day Teddy met a old man in his dream ,…

(i+1)*(j+1)=n+1 转换成上面这个式子,也就是问n+1的因子有几个 #include<cstdio> #include<cstring> #include<cmath> #include<algorithm> using namespace std; int main() { int T; scanf("%d",&T); while(T--) { long long n,y,i; scanf("%lld&qu…

题意: 给出一棵树,每条边有一个容量. 有若干次询问:\(S \, T \, K \, A \, B\),求路径\(S \to T\)的最大流量. 有两种方法可以增大流量: 花费\(A\)可以新修一条管道,管道可以连接任意两个点,两个点之间可以有任意条管道连接,新修的管道容量为\(1\) 花费\(B\)可以使某条管道(包括新修的管道)的容量增加\(1\) 求在不超过预算\(K\)的情况下的最大流量. 分析: 注意到流量最大只有\(10^4\),所以我们可以直接在值域上建一棵主席树. 主席树区间维…