hdu5713 K个联通块[2016百度之星复赛B题]

Posted 2020-07-16 XD-TEST

　　dp

　　代码

 1 #include<cstdio>
 2 const int N = 30000;
 3 const int P = 1000000009;
 4 int n,m,k,cnt[N];
 5 long long f[N],g[N],o[N],dp[N][15];
 6 int e[15][15],i,j,l,a,b;
 7 int check(int x,int y)
 8 {
 9     int i;
10     for (i=0;i<n;i++)
11     if ((1<<i)==x) break;
12     int tmp=i,ans=0;
13     for (i=0;i<n;i++)
14     if (((1<<i)|y)==y)
15     ans+=e[tmp][i];
16     return ans;
17 }
18 int main()
19 {
20     int test;
21     scanf("%d",&test); 
22     for (int ii=1;ii<=test;ii++)
23     {
24     scanf("%d%d%d",&n,&m,&l);
25     o[0]=1;for (i=1;i<=500;i++) o[i]=o[i-1]*2%P;
26     for (i=0;i<n;i++)
27     for (j=0;j<n;j++)
28     e[i][j]=0;
29     for (i=1;i<=m;i++)
30     {
31         scanf("%d%d",&a,&b);
32         a--;b--;
33         e[a][b]++;
34         if (a!=b)
35         e[b][a]++;
36     }
37     for (i=1;i<(1<<n);i++)
38         cnt[i]=cnt[i-(i&-i)]+check(i&-i,i);
39     for (i=0;i<(1<<n);i++)
40     f[i]=g[i]=0;
41     for (i=1;i<(1<<n);i++)
42     {
43         j=i;
44         do
45         {
46             j=((j-1)&i);
47             if ((j|(i&-i))==j)
48             g[i]=(g[i]+g[i-j]*f[j])%P;
49         } 
50         while (j!=i);
51         f[i]=(o[cnt[i]]-g[i])%P;
52         (g[i]+=f[i])%P;
53     }
54     for (i=1;i<(1<<n);i++)
55     for (k=1;k<=l;k++)
56     dp[i][k]=0;
57     dp[0][0]=1;
58     for (i=1;i<(1<<n);i++)
59     {
60         for (k=1;k<=l;k++)
61         {
62         j=i;
63         do
64         {
65             j=((j-1)&i);
66             if ((j|(i&-i))==j)
67             dp[i][k]=(dp[i][k]+dp[i-j][k-1]*f[j])%P;
68         } 
69         while (j!=i);
70         }
71     }
72     printf("Case #%d:\n%I64d\n",ii,(dp[(1<<n)-1][l]+P)%P);
73     }
74 }