/*{{{*/
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<string>
#include<iostream>
#include<sstream>
#include<set>
#include<map>
#include<queue>
#include<bitset>
#include<vector>
#include<limits.h>
#include<assert.h>
#define SZ(X) ((int)(X).size())
#define ALL(X) (X).begin(), (X).end()
#define REP(I, N) for (int I = 0; I < (N); ++I)
#define REPP(I, A, B) for (int I = (A); I < (B); ++I)
#define FOR(I, A, B) for (int I = (A); I <= (B); ++I)
#define FORS(I, S) for (int I = 0; S[I]; ++I)
#define RS(X) scanf("%s", (X))
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()), c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
#define GET_POS(c,x) (lower_bound(c.begin(),c.end(),x)-c.begin())
#define CASET int ___T; scanf("%d", &___T); for(int cs=1;cs<=___T;cs++)
#define MP make_pair
#define PB push_back
#define MS0(X) memset((X), 0, sizeof((X)))
#define MS1(X) memset((X), -1, sizeof((X)))
#define LEN(X) strlen(X)
#define F first
#define S second
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
typedef long double LD;
typedef pair<int,int> PII;
typedef vector<int> VI;
typedef vector<LL> VL;
typedef vector<PII> VPII;
typedef pair<LL,LL> PLL;
typedef vector<PLL> VPLL;
template<class T> void _R(T &x) { cin >> x; }
void _R(int &x) { scanf("%d", &x); }
void _R(LL &x) { scanf("%lld", &x); }
void _R(double &x) { scanf("%lf", &x); }
void _R(char &x) { scanf(" %c", &x); }
void _R(char *x) { scanf("%s", x); }
void R() {}
template<class T, class... U> void R(T &head, U &... tail) { _R(head); R(tail...); }
template<class T> void _W(const T &x) { cout << x; }
void _W(const int &x) { printf("%d", x); }
void _W(const LL &x) { printf("%lld", x); }
void _W(const double &x) { printf("%.16f", x); }
void _W(const char &x) { putchar(x); }
void _W(const char *x) { printf("%s", x); }
template<class T,class U> void _W(const pair<T,U> &x) {_W(x.F); putchar(' '); _W(x.S);}
template<class T> void _W(const vector<T> &x) { for (auto i = x.begin(); i != x.end(); _W(*i++)) if (i != x.cbegin()) putchar(' '); }
void W() {}
template<class T, class... U> void W(const T &head, const U &... tail) { _W(head); putchar(sizeof...(tail) ? ' ' : '\n'); W(tail...); }
#ifdef HOME
 #define DEBUG(...) {printf("# ");printf(__VA_ARGS__);puts("");}
#else
 #define DEBUG(...)
#endif
int MOD = 1e9+7;
void ADD(LL& x,LL v){x=(x+v)%MOD;if(x<0)x+=MOD;}
/*}}}*/
const int SIZE = 1e6+10;
int d[51][51];
bitset<51>e[20];
int eid[51][51],ee[51][2];
bool in(int x,int y,int z,int v){
    return d[x][y]==d[x][z]+d[z][y]&&d[x][y]==d[x][v]+d[v][y];
}
int get_bit(int x,int v){return (x>>v)&1;}
int main(){
    int N,M;
    R(N);
    FOR(i,1,N)FOR(j,1,N){
        if(i==j)d[i][j]=0;
        else d[i][j]=1e9;
    }
    REPP(i,1,N){
        int x,y;
        R(x,y);
        ee[i][0]=x;
        ee[i][1]=y;
        eid[x][y]=eid[y][x]=i;
        d[x][y]=d[y][x]=1;
    }
    FOR(k,1,N)FOR(i,1,N)FOR(j,1,N){
        d[i][j]=min(d[i][j],d[i][k]+d[k][j]);
    }
    R(M);
    REP(i,M){
        int x,y;
        R(x,y);
        REPP(j,1,N){
            if(in(x,y,ee[j][0],ee[j][1]))e[i][j]=1;
        }
    }
    LL an=0;
    REP(i,1<<M){
        bitset<51>now;
        int ng=1;
        REP(j,M){
            if(get_bit(i,j)){
                now|=e[j];
                ng=-ng;
            }
        }
        an+=ng*(1LL<<(N-1-now.count()));
    }
    W(an);
    return 0;
}


Measured memory_bytes: 256