几何的简单操作
摘要：点乘的几何意义是可以用来表征或计算两个向量之间的夹角，以及在b向量在a向量方向上的投影，有公式： a·b>0 方向基本相同，夹角在0°到90°之间 a·b=0 正交，相互垂直 a·b<0 方向基本相反，夹角在90°到180°之间 对于向量a和向量b： a和b的点积公式为： //矩阵乘法 #inclu
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posted @ 2019-09-09 21:31
随笔分类 - 几何
斜率最大的直线
摘要：https://www.jisuanke.com/contest/1230 3个点A,B,C,把它们的按x坐标排序。假设排序后的顺序是ABC，那么有两种情况：其中k()表示求斜率。 1.ABC共线，则k(AB)=k(BC)=k(AC) 2.ABC不共线，则ABC将形成一个三角形，那么k(AC) #include #include #include #include #includ...
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posted @ 2019-05-11 21:39
hdu 5533
摘要：Dancing Stars on Me Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 2460 Accepted Submission(s)
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posted @ 2018-09-11 20:11
牛客网 Wannafly挑战赛21 灯塔
摘要：Z市是一座港口城市，来来往往的船只依靠灯塔指引方向。在海平面上，存在n个灯塔。每个灯塔可以照亮以它的中心点为中心的90°范围。特別地， 由于特殊限制，每个灯塔照亮范围的角的两条边必须要么与坐标轴平行要么与坐标轴成45°。 由于经费限制，Z市的灯塔只能被点亮一座。你需要求出在这种情况下，是否存在一座灯
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posted @ 2018-08-11 10:56
hdu 6354
摘要：Problem Description Edward is a worker for Aluminum Cyclic Machinery. His work is operating mechanical arms to cut out designed models. Here is a brie
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posted @ 2018-08-07 21:27
ACM-ICPC 2017 Asia Urumqi G. The Mountain
摘要：All as we know, a mountain is a large landform that stretches above the surrounding land in a limited area. If we as the tourists take a picture of a
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posted @ 2018-07-29 20:49
hdu 2036
摘要：改革春风吹满地 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 29045 Accepted Submission(s): 14894 Prob
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posted @ 2018-07-29 13:55
Nordic Collegiate Programming Contest 2015 G. Goblin Garden Guards
摘要：In an unprecedented turn of events, goblins recently launched an invasion against the Nedewsian city of Mlohkcots. Goblins—small, green critters—love
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posted @ 2018-07-29 10:27
German Collegiate Programming Contest 2018 B. Battle Royale
摘要：Battle Royale games are the current trend in video games and Gamers Concealed Punching Circles (GCPC) is the most popular game of them all. The game t
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posted @ 2018-07-19 19:39
计蒜客 The 2018 ACM-ICPC Chinese Collegiate Programming Contest Rolling The Polygon
摘要：1 include 2 #include 3 #include 4 #include 5 #include 6 #include 7 #include 8 #include 9 #include 10 #include 11 #include 12 #include 13 typedef long long ll; 14 #define lowbit(x...
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posted @ 2018-07-18 20:10
