含[三点坐标计算面积].[判断两线段是否有交点].[求线段交点]模板   An Easy Problem?! Time Limit: 1000MS   Memory Limit: 65536K Total Submissions:15921   Accepted: 2459 Description It's raining outside. Farmer Johnson's bull Ben wants some rain to water his flowers. Ben nails two…

呵呵哒.WA了无数次,一开始想的办法最终发现都有缺陷.首先需要知道: 1)线段不相交,一定面积为0 2)有一条线段与X轴平行,面积一定为0 3)线段相交,但是能接水的三角形上面线段把下面的线段完全覆盖. (1),(2)的情况简单,主要是解决(3).下面对(3)进行讨论,如下图所示,设p1,p2是两线段各自位置较高的点,p0为两线段的交点,向量e是三角形p0p1p2的关于边p1p2的外侧法向量.则当e的终点位于第1,2象限时才会有积水,3,4象限是没有的.判断e的方向可以根据它与(p0p1+p0p…

传送门 •题意 两根木块组成一个槽,给定两个木块的两个端点 雨水竖直下落,问槽里能装多少雨水, •思路 找不能收集到雨水的情况 我们令线段较高的点为s点,较低的点为e点 ①两条木块没有交点 ②平行或重合 ③至少有一条木块水平(雨水会滑落) ④形成覆盖,如"$\wedge $","人",还有比较难想的上边长下边短的情况 其中形成"$\wedge$"型和"人"型 都是两条线段的交点比两条线段中较低的s点同高,     也就是不大于…

Problem E Easy Problem from Rujia Liu? Though Rujia Liu usually sets hard problems for contests (for example, regional contests like Xi'an 2006, Beijing 2007 and Wuhan 2009, or UVa OJ contests like Rujia Liu's Presents 1 and 2), he occasionally sets…

An easy problem Time Limit:3000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status 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 d…

Easy Problem from Rujia Liu? Though Rujia Liu usually sets hard problems for contests (for example, regional contests like Xi'an 2006, Beijing 2007 and Wuhan 2009, or UVa OJ contests like Rujia Liu's Presents 1 and 2), he occasionally sets easy probl…

An Easy Problem?! Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 7837   Accepted: 1145 Description It's raining outside. Farmer Johnson's bull Ben wants some rain to water his flowers. Ben nails two wooden boards on the wall of his barn…

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…

UVa11991 Easy Problem from Rujia Liu?  思路:  构造数组data,使满足data[v][k]为第k个v的下标.因为不是每一个整数都会出现因此用到map,又因为每个数出现次数不等可能相差很大,因此用到vector. 注意:对于数据的清空与判空不要忘记,而map在调用之前必须有map.count的检查. 代码: #include<cstdio> #include<map> #include<vector> using namespac…

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,…