XVIII Open Cup named after E.V. Pankratiev. GP of SPb

Posted 2020-11-24 fst-stay-night

contest Link

A. Base i ? 1 Notation

solved by sdcgvhgj 238

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B. Squaring a Bit

solved by rdc 77

本地打表，交表。

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C. Chickens

solved by rdc, 24

f[i][mask] 表示前 i 个物品匹配 mask 集合的方案数。

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D. Lights at a Crossing

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E. Decimal Form

solved by rdc, 247 -2

类欧或者SB树，然后发现自己写的类欧板子炸掉了。

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F. Martian Maze

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G. Wet Mole

solved by F0_0H, 58

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H. Oddities

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I. Sorting on the Plane

solved by rdc 150 -2

同一个半平面的一些向量，可以直接 sort 确定两两大小关系。任选一个向量，其左侧的向量一定在同一半平面，右侧亦然。比较左侧最左和右侧最右，即可判定是否成环。

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J. Center of List of Sums

solved by sdcgvhgj 87 -1

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K. Cookies

solved by F0_0H 214 -2

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L. Xor-fair Division

solved by rdc, 5

签到。

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