03 2022 档案
摘要:二分图的定义 如果一张无向图的 N 个节点(N ≥ 2) 可以分成 A,B 两个非空集合,其中A∩B=Ø,并且在同一个集合内的点之间都没有边相连,那么称这张无向图为一张二分图。A,B 分别称为二分图的左部和右部。 二分图的一些性质: 1.图中不存在奇环。(证明,二分图构成环,必然是 A-B-A 之类
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摘要:题意 一个矩形中,有n个城市’*’,现在这n个城市都要覆盖无线,若放置一个基站,那么它至多可以覆盖相邻的两个城市。 问至少放置多少个基站才能使得所有的城市都覆盖无线? 分析 每一个城市都需要被一个基站覆盖,而一个基站最多覆盖两个城市。为了使基站的数量最少,我们可以考虑让尽可能多的基站覆盖两个城市。设
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摘要:题面 Accounting for Computer Machinists (ACM) has sufferred from the Y2K bug and lost some vital data for preparing annual report for MS Inc. All what t
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摘要:题面 Assume the coasting is an infinite straight line. Land is in one side of coasting, sea in the other. Each small island is a point locating in the s
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摘要:题面 The game “The Pilots Brothers: following the stripy elephant” has a quest where a player needs to open a refrigerator. There are 16 handles on the
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摘要:题面 Flip game is played on a rectangular 4x4 field with two-sided pieces placed on each of its 16 squares. One side of each piece is white and the othe
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