#include <iostream>
#include <vector>
#include <string>
#include <iomanip>
#include <queue>
#include <cmath>
#include <algorithm>
#include <unordered_map>
#include <tuple>
#include <iomanip>
#include <stdio.h>
#include <map>
#include <bitset>
#include <set>
#include <stack>
#include <queue>
#include <unordered_set>
#include <cassert>
#include <stdlib.h>
#include <time.h>
#include <random>


//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,sse3,sse4")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("fast-math")
//#pragma GCC target("avx2")
//#pragma GCC optimize("section-anchors")
//#pragma GCC optimize("profile-values,profile-reorder-functions,tracer")
//#pragma GCC optimize("vpt")
//#pragma GCC optimize("rename-registers")
//#pragma GCC optimize("move-loop-invariants")
//#pragma GCC optimize("unswitch-loops")
//#pragma GCC optimize("function-sections")
//#pragma GCC optimize("data-sections")

#define int long long
#define ll long long
#define ull unsigned long long
#define all(a) (a).begin(), (a).end()
#define pii pair<int, int>
#define pb push_back
#define ld long double


using namespace std;

//const int INF = 1e17;
//const int mod = 2600000069;
//const int p = 179;
const int MAXN = 2e5 + 1;
const int logn = 19;

int n;
int here[MAXN], after[MAXN], tin[MAXN], tout[MAXN], up[MAXN][logn];
vector<int> g[MAXN];
int timer = 0;

void dfs(int v, int p) {
    up[v][0] = p;
    for (int i = 1; i < logn; i++) {
        up[v][i] = up[up[v][i - 1]][i - 1];
    }
    tin[v] = timer++;
    for (auto u : g[v]) {
        if (u != p) dfs(u, v);
    }
    tout[v] = timer;
}

bool ancestor(int u, int v) {
    return tin[u] <= tin[v] && tout[u] >= tout[v];
}

int ans = 0;
void dfs1(int v, int p, int cur) {
    cur += here[v];
//    cout << v << " " << here[v] << "\n";
//    cout << v << " : " << cur << "\n";
    ans = max(cur, ans);
    for (auto u : g[v]) {
        if (u != p) {
            dfs1(u, v, cur);
        }
    }
}

int lst(int v, int u) {
    if (ancestor(u, v)) {
        for (int i = logn - 1; i >= 0; i--) {
            if (!ancestor(up[v][i], u)) v = up[v][i];
        }
        return v;
    } else {
        for (int i = logn - 1; i >= 0; i--) {
            if (!ancestor(up[u][i], v)) u = up[u][i];
        }
        return u;
    }
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n;
    int u, v;
    for (int i = 0; i < n - 1; i++) {
        cin >> u >> v;
        u--;v--;
        g[u].pb(v);
        g[v].pb(u);
    }
    dfs(0, 0);
    int m;
    cin >> m;
    for (int i = 0; i < m; i++) {
        cin >> u >> v;
        u--;v--;
        if (ancestor(u, v)) {
//            cout << "here1\n";
            here[0]++;
            int l = lst(u, v);
            here[l]--;
            here[v]++;
        } else if (ancestor(v, u)) {
//            cout << "here2\n";
            here[0]++;
            int l = lst(u, v);
            here[l]--;
            here[u]++;
        } else {
            here[u]++;
            here[v]++;
        }
    }
//    for (int i = 0; i < n; i++) {
//        cout << i << " : " << here[i] << " " << after[i] << "\n";
//    }
//    cout << "\n";
    dfs1(0, 0, 0);
    cout << ans;
}
/*
4
1 2
1 3
1 4
2
1 4
2 3
-> 2
*/