P3349 [ZJOI2016]小星星

#include<bits/stdc++.h>
#define Tp template<typename Ty>
#define Ts template<typename Ty,typename... Ar>
#define W while
#define I inline
#define RI register int
#define LL long long
#define Cn const
#define CI Cn int&
#define gc getchar
#define D isdigit(c=gc())
#define pc(c) putchar((c))
#define min(x,y) ((x)<(y)?(x):(y))
#define max(x,y) ((x)>(y)?(x):(y))
using namespace std;
namespace Debug{
    Tp I void _debug(Cn char* f,Ty t){cerr<<f<<'='<<t<<endl;}
    Ts I void _debug(Cn char* f,Ty x,Ar... y){W(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
    Tp ostream& operator<<(ostream& os,Cn vector<Ty>& V){os<<"[";for(Cn auto& vv:V) os<<vv<<",";os<<"]";return os;}
    #define gdb(...) _debug(#__VA_ARGS__,__VA_ARGS__)
}using namespace Debug;
namespace FastIO{
    Tp I void read(Ty& x){char c;int f=1;x=0;W(!D) f=c^'-'?1:-1;W(x=(x<<3)+(x<<1)+(c&15),D);x*=f;}
    Ts I void read(Ty& x,Ar&... y){read(x),read(y...);}
    Tp I void write(Ty x){x<0&&(pc('-'),x=-x,0),x<10?(pc(x+'0'),0):(write(x/10),pc(x%10+'0'),0);}
    Tp I void writeln(Cn Ty& x){write(x),pc('\n');}
}using namespace FastIO;
Cn int N=18;
int n,m,H[N][N],A[N];
vector<int> G[N],V;
LL Ans,F[N][N];
I int Count(RI x){RI X=0;W(x) x-=(x&-x),X++;return X;}
I void Dfs(CI x,CI fa){
    LL X;for(auto i:G[x]) i^fa&&(Dfs(i,x),0);
    for(auto i:V){F[x][i]=1;for(auto j:G[x]) if(j^fa){X=0;for(auto k:V) if(i^k&&H[i][k]) X+=F[j][k];F[x][i]*=X;}}
}
I LL S(CI x){
    RI i;LL X=0;for(V.clear(),memset(A,0,sizeof(A)),i=1;i<=n;i++) x>>(i-1)&1&&(V.push_back(i),A[i]=1);
    Dfs(1,0);for(auto i:V) X+=F[1][i];return X;
}
int main(){
    RI i,x,y;for(read(n,m),i=1;i<=m;i++) read(x,y),H[x][y]=H[y][x]=1;
    for(i=1;i<n;i++) read(x,y),G[x].push_back(y),G[y].push_back(x);
    for(i=0;i<(1<<n);i++) Ans+=((n-Count(i))&1?-S(i):S(i));return writeln(Ans),0;
}