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#include <iostream>
#include <vector>
#include <queue>
#include <cstring>
using namespace std;
typedef long long ll;

const int MAXN = 55; // 顶点数
const int MAXM = 20; // 约束数
vector<pair<int, int>> G[MAXN]; // 树：邻接表存 (to, edge_id)

ll edge_mask[MAXM]; // 第i个约束路径对应的边集合（二进制mask）
int N, M;

// BFS 找 u->v 路径上的所有边，返回二进制mask
ll get_path_mask(int u, int v) {
queue<int> q;
int from[MAXN], eid[MAXN]; // from: 前驱点 eid: 前驱边
memset(from, -1, sizeof(from));
q.push(u);
from[u] = u;

while (!q.empty()) {
    int x = q.front(); q.pop();
    if (x == v) break;
    for (auto [y, id] : G[x]) {
        if (from[y] == -1) {
            from[y] = x;
            eid[y] = id;
            q.push(y);
        }
    }
}

// 回溯路径，收集边
ll mask = 0;
int cur = v;
while (cur != u) {
    mask |= 1LL << eid[cur];
    cur = from[cur];
}
return mask;

}

int main() {
ios::sync_with_stdio(false);
cin.tie(0);

cin >> N;
// 给边编号 0 ~ N-2
for (int i = 0; i < N-1; i++) {
    int a, b;
    cin >> a >> b;
    G[a].emplace_back(b, i);
    G[b].emplace_back(a, i);
}

cin >> M;
for (int i = 0; i < M; i++) {
    int u, v;
    cin >> u >> v;
    edge_mask[i] = get_path_mask(u, v);
}

// 容斥原理：枚举所有子集
ll ans = 0;
for (int s = 0; s < (1 << M); s++) {
    int cnt = __builtin_popcount(s); // 子集大小
    ll union_e = 0;                  // 这些约束对应的边的并集
    
    // 合并所有选中约束的边集
    for (int i = 0; i < M; i++) {
        if (s & (1 << i)) union_e |= edge_mask[i];
    }
    
    ll free = (N-1) - __builtin_popcountll(union_e);
    ll ways = 1LL << free;
    
    // 容斥系数：(-1)^cnt
    if (cnt % 2 == 0) ans += ways;
    else ans -= ways;
}

cout << ans << endl;
return 0;

}