poj 1185

状压DP。。。没好好去想转移方程推掉了重写QAQ

对状态数目的优化还是挺牛的orz

 1 //#include<bits/stdc++.h>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<iostream>
 5 #include<queue>
 6 #include<algorithm>
 7 #define inc(i,l,r) for(int i=l;i<=r;i++)
 8 #define dec(i,l,r) for(int i=l;i>=r;i--)
 9 #define link(x) for(edge *j=h[x];j;j=j->next)
10 #define mem(a) memset(a,0,sizeof(a))
11 #define inf 1e9
12 #define ll long long
13 #define succ(x) (1<<x)
14 #define NM 60+5
15 using namespace std;
16 int read(){
17     int x=0,f=1;char ch=getchar();
18     while(!isdigit(ch)){if(ch==‘-‘)f=-1;ch=getchar();}
19     while(isdigit(ch))x=x*10+ch-‘0‘,ch=getchar();
20     return x*f;
21 }
22 bool _read(){
23     char c=getchar();
24     while(c!=‘P‘&&c!=‘H‘)c=getchar();
25     return c==‘H‘;
26 }
27 int d[105][NM][NM],c[NM],b[NM],n,m,a[105],s,ans;
28 int cou(int t){
29     int s=0;
30     inc(j,0,10)
31     if(t&succ(j))s++;
32     return s;
33 }
34 int main(){
35     n=read();m=read();
36     inc(i,1,n)
37     inc(j,1,m)
38     if(_read())a[i]+=succ(j-1);
39     inc(t,0,succ(m)-1)
40     if(!(t&(t<<1))&&!(t&(t<<2)))
41     b[++s]=t,c[s]=cou(t);
42     if(n==1){
43         inc(i,1,s)
44         if(!(b[i]&a[1]))
45         ans=max(ans,c[i]);
46         printf("%d\n",ans);
47         return 0;
48     }
49     inc(t,1,s)
50     if(!(b[t]&a[2])){
51         inc(v,1,s)
52         if(!(b[v]&a[1])&&!(b[v]&b[t]))
53         d[2][t][v]=c[t]+c[v];
54     }
55     inc(i,3,n)
56     inc(t,1,s)
57     if(!(b[t]&a[i])){
58         inc(v,1,s)
59         if(!(b[v]&b[t])&&!(b[v]&a[i-1])){
60         d[i][t][v]=c[t]+c[v];
61         inc(j,1,s)
62         if(d[i-1][v][j]&&!(b[t]&b[j])&&!(b[j]&a[i-2]))
63         d[i][t][v]=max(d[i][t][v],d[i-1][v][j]+c[t]);
64         }
65     }
66     inc(i,1,s)
67     inc(j,1,s)
68     ans=max(ans,d[n][i][j]);
69     printf("%d\n",ans);
70     return 0;
71 }