vs(i)表示患i这种疾病的牛的集合. f(S)表示S集合的病被多少头牛患了. 枚举不在S中的疾病i,把除了i和S之外的所有病的牛集合记作St. f(S|i)=max{f(S)+((St|vs(i))^St)中牛的数量} #include<cstdio> #include<bitset> #include<algorithm> using namespace std; bitset<1000>vs[15],t,t2; int n,m,K,ans,f[1<…

思路:状压dp,枚举疾病的集合,然后判断一下可行性即可. #include<bits/stdc++.h> using namespace std; #define maxs 400000 #define maxn 1900 int n,d,k; int a[maxn],f[maxs],num[maxs]; int main(){ scanf("%d%d%d",&n,&d,&k); ;i<(<<d);i++) num[i]=num[i…

[BZOJ1688][Usaco2005 Open]Disease Manangement 疾病管理 Description Alas! A set of D (1 <= D <= 15) diseases (numbered 1..D) is running through the farm. Farmer John would like to milk as many of his N (1 <= N <= 1,000) cows as possible. If the mil…

我一开始写了个状压dp..然后没有滚动就MLE了... 其实这道题直接暴力就行了... 2^15枚举每个状态, 然后检查每头牛是否能被选中, 这样是O( 2^15*1000 ), 也是和dp一样的时间复杂度....有点贪心的feel ------------------------------------------------------------------------------ #include<cstdio> #include<algorithm> #include&l…

1688: [Usaco2005 Open]Disease Manangement 疾病管理 Time Limit: 5 Sec  Memory Limit: 64 MBSubmit: 413  Solved: 275[Submit][Status][Discuss] Description Alas! A set of D (1 <= D <= 15) diseases (numbered 1..D) is running through the farm. Farmer John woul…

分析: 这个题的状压DP还是比较裸的,考虑将疾病状压,得到DP方程:F[S]为疾病状态为S时的最多奶牛数量,F[S]=max{f[s]+1}; 记得预处理出每个状态下疾病数是多少... 附上代码: #include <cstdio> #include <algorithm> #include <cmath> #include <cstdlib> #include <cstring> #include <queue> #include…

题目描述 Alas! A set of D (1 <= D <= 15) diseases (numbered 1..D) is running through the farm. Farmer John would like to milk as many of his N (1 <= N <= 1,000) cows as possible. If the milked cows carry more than K (1 <= K <= D) different d…

题目描述 Alas! A set of D (1 <= D <= 15) diseases (numbered 1..D) is running through the farm. Farmer John would like to milk as many of his N (1 <= N <= 1,000) cows as possible. If the milked cows carry more than K (1 <= K <= D) different d…

Description Alas! A set of D (1 <= D <= 15) diseases (numbered 1..D) is running through the farm. Farmer John would like to milk as many of his N (1 <= N <= 1,000) cows as possible. If the milked cows carry more than K (1 <= K <= D) diff…

http://www.lydsy.com/JudgeOnline/problem.php?id=1688 很水的状压.. 提交了很多次优化的,但是还是100msT_T #include <cstdio> #include <cstring> #include <cmath> #include <string> #include <iostream> #include <algorithm> #include <queue>…