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#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<map>
#include<stack>
#include<cmath>
#include<set>
#include<bitset>
#include<complex>
#include<cstdlib>
#include<assert.h>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define mem(a) memset(a,0,sizeof(a))
#define ll long long
#define eps 1e-8
#define succ(x) (1<<(x))
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define mp make_pair
#define pb push_back
#define NM 18
#define nm 289
using namespace std;
const double pi=acos(-1);
const ll inf=1e9+7;
ll read(){
ll x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
struct edge{int t;edge*next;}e[nm],*h[NM],*o=e;
void add(int x,int y){o->t=y;o->next=h[x];h[x]=o++;}
vector<int>vec,ed[NM];
int n,m,_x,_y,tot;
ll ans,d[NM][NM];
bool v[NM];
void dfs(int x,int f=0){
for(int&i:vec)d[x][i]=1;
link(x)if(j->t!=f){
dfs(j->t,x);
for(int&i:vec){
ll s=0;
for(int&k:ed[i])if(v[k])s+=d[j->t][k];
d[x][i]=d[x][i]*s;
}
}
}
int main(){
n=read();m=read();
while(m--){
_x=read();_y=read();
ed[_x].push_back(_y);
ed[_y].push_back(_x);
}
inc(i,2,n){
_x=read();_y=read();
add(_x,_y);add(_y,_x);
}
tot=succ(n)-1;
inc(i,1,tot){
vec.clear();mem(v);
inc(j,1,n)if(i>>(j-1)&1)vec.push_back(j),v[j]++;
dfs(1);
for(int&j:vec)
if(__builtin_popcount(i^tot)&1)ans-=d[1][j];
else ans+=d[1][j];
}
printf("%lld\n",ans);
return 0;
}
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