计算几何……不会啊 我们定义 $x$$y$ 的叉积是 $|x||y| sin$ 用坐标表示就是 $x1y2 x2y1$ 根据叉积可以判断两个的夹角 然后维护一个上凸壳和下凸壳，就可以求出凸包的周长了。 ...
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其他好文 时间：
2020-05-02 19:13:31
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61
B - Dining POJ - 3281 首先二分图的多重匹配匈牙利算法是不行的，无法最优。 直接在 ...
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2020-05-01 16:40:34
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42
"题目" For their physical fitness program, $N (2 ≤ N ≤ 1,000,000)$ cows have decided to run a relay race using the $T (2 ≤ T ≤ 100)$ cow trails througho ...
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2020-04-28 15:29:35
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57
Farmer John has decided to reward his cows for their hard work by taking them on a tour of the big city! The cows must decide how best to spend their ...
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2020-04-10 15:56:32
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76
题目 Farmer John has arranged his N (1 ≤ N ≤ 5,000) cows in a row and many of them are facing forward, like good cows. Some of them are facing backward, ...
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2020-04-06 17:13:28
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68
题目 Farmer John has arranged his N (1 ≤ N ≤ 5,000) cows in a row and many of them are facing forward, like good cows. Some of them are facing backward, ...
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2020-04-06 09:56:48
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80
题目描述 Farmer John has arranged his N (1 ≤ N ≤ 5,000) cows in a row and many of them are facing forward, like good cows. Some of them are facing backwar ...
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2020-04-06 00:23:00
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298
Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Be ...
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2020-03-30 00:21:16
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101
题目描述 The cows are being invaded! Their republic comprises N (1 <= N <= 50,000) towns that are connected by M (1 <= M <= 100,000) undirected paths betw ...
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2020-03-24 09:16:45
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78
Farmer John knows that an intellectually satisfied cow is a happy cow who will give more milk. He has arranged a brainy activity for cows in which the ...
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其他好文 时间：
2020-03-23 13:47:05
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74
