04 2015 档案
摘要:这道题目是13山东省省赛的签到题,题目大意是给等边三角形的两个定点,让求逆时针旋转之后的第三个点的坐标,原来不会向量的旋转,在网上找了找,找到一篇挺好的,直接贴过来。向量的旋转实际做题中我们可能会遇到很多有关及计算几何的问题,其中有一类问题就是向量的旋转问题,下面我们来具体探讨一下有关旋转的问题。首...
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摘要:EscapeTime Limit: 20000/10000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 598Accepted Submission(s): 153Problem Desc...
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摘要:SticksTime Limit:1000MSMemory Limit:10000KTotal Submissions:125918Accepted:29372DescriptionGeorge took sticks of the same length and cut them randomly...
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摘要:AreaTime Limit:1000MSMemory Limit:10000KTotal Submissions:5227Accepted:2342DescriptionBeing well known for its highly innovative products, Merck would...
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摘要:Scrambled PolygonTime Limit:1000MSMemory Limit:30000KTotal Submissions:7214Accepted:3445DescriptionA closed polygon is a figure bounded by a finite nu...
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摘要:WallTime Limit:1000MSMemory Limit:10000KTotal Submissions:31199Accepted:10521DescriptionOnce upon a time there was a greedy King who ordered his chief...
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摘要:Space AntTime Limit:1000MSMemory Limit:10000KTotal Submissions:3316Accepted:2118DescriptionThe most exciting space discovery occurred at the end of th...
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摘要:Largest Rectangle in a HistogramTime Limit:1000MSMemory Limit:65536KTotal Submissions:15831Accepted:5121DescriptionA histogram is a polygon composed o...
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摘要:Cupid's ArrowTime Limit: 3000/1000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1163Accepted Submission(s): 425Proble...
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摘要:A Round Peg in a Ground HoleTime Limit:1000MSMemory Limit:10000KTotal Submissions:5456Accepted:1735DescriptionThe DIY Furniture company specializes in...
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摘要:题目大意: 给定你n个数, 其中有n-2个数都是两两成对的,有两个是单独出现的,如n = 8, 2 3 2 5 3 6 4 6, 这时候4和5是单独的两个,所以答案就是4,5,其中n的范围是1e6.思路: 之前做过找一个单独的数的题,那个题是用一个比较巧妙的方法来做的,不过这个也是一类经典问题,用到...
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摘要:最高的奖励时间限制:1000ms | 内存限制:65535KB难度:3描述请问:挖掘机技术哪家强?AC了告诉你!给你N(N#include #include #include #include using namespace std;const int N = 50005;bool vis[N];s...
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摘要:Pick-up sticksTime Limit:3000MSMemory Limit:65536KTotal Submissions:10330Accepted:3833DescriptionStan has n sticks of various length. He throws them o...
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摘要:The DoorsTime Limit:1000MSMemory Limit:10000KTotal Submissions:6734Accepted:2670DescriptionYou are to find the length of the shortest path through a c...
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摘要:两条直线可能有三种关系:1.共线 2.平行(不包括共线) 3.相交。 那给定两条直线怎么判断他们的位置关系呢。还是用到向量的叉积例题:POJ1269题意:这道题是给定四个点p1, p2, p3, p4,直线L1,L2分别穿过前两个和后两个点。来判断直线L1和L2的关系这三种关系一个一个来看:1....
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摘要:题意:在二维平面中,给定一些线段,然后判断在某直线上的投影是否有公共点。转化,既然是投影,那么就是求是否存在一条直线L和所有的线段都相交。证明:下面给出具体的分析:先考虑一个特殊的情况,即n=1的时候,如下图,线段AB在直线L上的投影为线段A'B',则过任意介于A'B'之间的点C'做直线L的垂线必交...
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摘要:POJ 2318:题目大意:给定一个盒子的左上角和右下角坐标,然后给n条线,可以将盒子分成n+1个部分,再给m个点,问每个区域内有多少各点这个题用到关键的一步就是向量的叉积,假设一个点m在 由abcd围成的四边形区域内,那么向量ab, bc, cd, da和点的关系就是,点都在他们的同一侧,我是按照...
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