//https://atcoder.jp/contests/abc152/tasks/abc152_f
#include <bits/stdc++.h>
using namespace std;

#define el '\n'
#define pb push_back
#define sp ' '
#define all(x) (x).begin(), (x).end()
#define mset(x, y) memset(x, y, sizeof(x))
#define ff first
#define ss second

// clang-format off
#ifndef ONLINE_JUDGE
template <typename T, size_t N> int SIZE(const T (&t)[N]){ return N; } template<typename T> int SIZE(const T &t){ return t.size(); } string to_string(const string s, int x1=0, int x2=1e9){ return '"' + ((x1 < (int)s.size()) ? s.substr(x1, x2-x1+1) : "") + '"'; } string to_string(const char* s) { return to_string((string) s); } string to_string(const bool b) { return (b ? "true" : "false"); } string to_string(const char c){ return string({c}); } template<size_t N> string to_string(const bitset<N> &b, int x1=0, int x2=1e9){ string t = ""; for(int __iii__ = min(x1,SIZE(b)),  __jjj__ = min(x2, SIZE(b)-1); __iii__ <= __jjj__; ++__iii__){ t += b[__iii__] + '0'; } return '"' + t + '"'; } template <typename A, typename... C> string to_string(const A (&v), int x1=0, int x2=1e9, C... coords); int l_v_l_v_l = 0, t_a_b_s = 0; template <typename A, typename B> string to_string(const pair<A, B> &p) { l_v_l_v_l++; string res = "(" + to_string(p.first) + ", " + to_string(p.second) + ")"; l_v_l_v_l--; return res; } template <typename A, typename... C> string to_string(const A (&v), int x1, int x2, C... coords) { int rnk = rank<A>::value; string tab(t_a_b_s, ' '); string res = ""; bool first = true; if(l_v_l_v_l == 0) res += el; res += tab + "["; x1 = min(x1, SIZE(v)), x2 = min(x2, SIZE(v)); auto l = begin(v); advance(l, x1); auto r = l; advance(r, (x2-x1) + (x2 < SIZE(v))); for (auto e = l; e != r; e = next(e)) { if (!first) { res += ", "; } first = false; l_v_l_v_l++; if(e != l){ if(rnk > 1) { res += el; t_a_b_s = l_v_l_v_l; }; } else{ t_a_b_s = 0; } res += to_string(*e, coords...); l_v_l_v_l--; } res += "]"; if(l_v_l_v_l == 0) res += el; return res; } void dbgm(){;} template<typename Heads, typename... Tails> void dbgm(Heads H, Tails... T){ cout << to_string(H) << " | "; dbgm(T...); } 
#define dbg(...) cout << "[" << #__VA_ARGS__ << "]: "; cout << to_string(__VA_ARGS__) << endl
#define dbgm(...) cout << "[" << #__VA_ARGS__ << "]: "; dbgm(__VA_ARGS__); cout << endl
#else
#define dbg(...) ;
#define dbgm(...) ;
#endif
// clang-format on

typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<pii, pii> ppi;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pii> vpii;
typedef vector<vi> vvi;
typedef vector<vll> vvll;

const int inf = 1e09 + 5e3;
const ll linf = 2e18 + 5e3;
const int mod = 1e9 + 7;
const int mxn = 60;

int n, m, offset;
vvi adj;
map<pii, int> ma;
int mask[mxn];

ll memo[mxn][(1 << 20) + 30];

void id(int a, int b)
{
    if (!~a || !~b)
        return;
    if (a > b)
        swap(a, b);
    auto it = ma.find({a, b});
    if (it == ma.end())
        ma[{a, b}] = (1 << offset);
    else
        it->second |= (1 << offset);
}

int dfs(int v, int p, int target)
{
    for (auto u : adj[v])
    {
        if (u == p)
            continue;
        if (u == target)
        {
            id(v, u);
            return 1;
        }
        if (dfs(u, v, target))
        {
            id(v, u);
            return 1;
        };
    }
    return 0;
}

ll dp(int i, int msk)
{
    if (i == n - 1)
        return __builtin_popcount(msk) == m;
    if (~memo[i][msk])
        return memo[i][msk];
    ll ret = dp(i + 1, msk);
    ret += dp(i + 1, msk | mask[i]);
    return memo[i][msk] = ret;
}

int main()
{
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    mset(mask, 0);
    mset(memo, -1);
    cin >> n;
    adj.assign(n, vi());
    int temp, temp2;
    for (int i = 0; i < n - 1; i++)
    {
        cin >> temp >> temp2;
        temp--, temp2--;
        adj[temp].pb(temp2);
        adj[temp2].pb(temp);
    }
    cin >> m;
    for (int i = 0; i < m; i++)
    {
        cin >> temp >> temp2;
        temp--, temp2--;
        offset = i;
        dfs(temp, -1, temp2);
    }
    int ind = 0;
    for (auto blah : ma)
        mask[ind++] = blah.ss;

    cout << dp(0, 0);
}


Measured memory_bytes: 495092