因为上次比赛sb地把一道树形dp当费用流做了,受了点刺激,用一天时间稍微搞一下树形DP,今后再好好搞一下) 基于背包原理的树形DP poj 1947 Rebuilding Roads 题意:给你一棵树,让你求最少剪掉多少条边可以剪出一棵点数为m的子树. 解法:dp[i][j]表示i节点得到j个节点的 ...
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其他好文 时间:
2017-05-26 18:56:32
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274
The kingdom of Olympia consists of N cities and M bidirectional roads. Each road connects exactly two cities and two cities can be connected with more ...
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其他好文 时间:
2017-05-26 00:42:36
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283
Rebuilding Roads Time Limit: 1000MS Memory Limit: 30000K Total Submissions: 9957 Accepted: 4537 Description The cows have reconstructed Farmer John's ...
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其他好文 时间:
2017-05-21 16:02:14
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168
题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2586 Problem Description There are n houses in the village and some bidirectional roads connecting them ...
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其他好文 时间:
2017-05-21 09:59:42
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242
It's almost summer time, and that means that it's almost summer construction time! This year, the good people who are in charge of the roads on the tr ...
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其他好文 时间:
2017-05-20 22:34:40
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237
近期一次pat考试中的最后一题。事实上玩算法这东西就像打魔兽。不能光有思想上的高度,微操必须实打实。就这么个迪杰斯特拉算法。多少教科书上都讲烂了。可是现场又有多少人是敲对的呢?不能光停留在理解上。必须能用自己的方式表达出来才算过关。 题目: 1087. All Roads Lead to Rome ...
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其他好文 时间:
2017-05-15 19:46:36
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233
A. Asphalting Roads(模拟) City X consists of n vertical and n horizontal infinite roads, forming n?×?n intersections. Roads (both vertical and horizonta ...
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其他好文 时间:
2017-05-08 21:59:49
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194
Constructing Roads Description There are N villages, which are numbered from 1 to N, and you should build some roads such that every two villages can ...
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其他好文 时间:
2017-05-08 10:10:02
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203
Constructing Roads 这道题很水,就是一个裸的最小生成树,最不过把已经连接的节点的值再设为0。 代码: 1 #include<cstdio> 2 #include<cstring> 3 #define N 1010 4 int dis[N][N],minn[N],n,m,a,b; 5 ...
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其他好文 时间:
2017-05-07 21:58:58
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104
最小生成树问题。 Kruskal。假设已经有边就合并。 然后找最小。没有坑点。 G++ AC。 #include<cstdio> #include<cstring> #include<queue> #include<algorithm> #include<queue> #include<map> # ...
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其他好文 时间:
2017-05-07 21:15:09
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139