//Nguyen Huu Hoang Minh
#include <bits/stdc++.h>
#define sz(x) int(x.size())
#define all(x) x.begin(),x.end()
#define reset(x) memset(x, 0,sizeof(x))
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define N 200005
#define remain(x) if (x > MOD) x -= MOD
#define ii pair<int, int>
#define iiii pair< ii , ii >
#define viiii vector< iiii >
#define vi vector<int>
#define vii vector< ii >
#define bit(x, i) (((x) >> (i)) & 1)
#define Task "test"

using namespace std;

typedef long double ld;

int n, m;
vector<int> g[N];

void readfile()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    if (fopen(Task".inp","r"))
    {
        freopen(Task".inp","r",stdin);
        //freopen(Task".out","w",stdout);
    }
    cin >> n;
    for(int i=1; i<n; i++){
        int u, v; cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }
}

int Start[N], Depth[N], Time, Par[N];
ii RMQ[21][N*2];

void DFS(int u, int p=-1){
    Start[u] = ++Time;
    RMQ[0][Time] = ii(Depth[u], u);
    for (int v : g[u]){
        if (v != p){
            Depth[v] = Depth[u] + 1;
            Par[v] = u;
            DFS(v, u);
            RMQ[0][++Time] = ii(Depth[u], u);
        }
    }
}

void Preprocess(){
    DFS(1);
    int LIM = log2(Time);
    for (int i = 1; i <= LIM; ++i){
        for (int j = 1; j + (1 << i) - 1 <= Time; ++j){
            RMQ[i][j] = min(RMQ[i-1][j], RMQ[i-1][j + (1 << (i-1))]);
        }
    }
}

int LCA(int u, int v){
    int Left = min(Start[u], Start[v]);
    int Right = max(Start[u], Start[v]);
    int len = log2(Right - Left + 1);
    return min(RMQ[len][Left], RMQ[len][Right - (1 << len) + 1]).se;
}

int ans = 0, vst[N];

void fix(int u, int par){
    for(auto v : g[u]){
        if (v==par) continue;
        fix(v,u);
        vst[u] += vst[v];
    }
    if (vst[u]==0) ans++;
}

void proc()
{
    Preprocess();
    cin >> m;
    for(int i=1; i<=m; i++){
        int u, v, z;
        cin >> u >> v;
        z = LCA(u,v);
        vst[u]++; vst[v]++;
        vst[z]--; vst[Par[z]]--;
    }
    fix(1,1);
    cout << ans;
}

signed main()
{
    readfile();
    proc();
    return 0;
}