//Let's join Kaede Takagaki Fan Club !!
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
//#define int long long
typedef long long ll;
typedef pair<int,int> P;
typedef pair<int,P> P1;
typedef pair<P,P> P2;
#define pu push
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define eps 1e-7
#define INF 1000000000
#define a first
#define b second
#define fi first
#define sc second
#define rng(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,x) for(int i=0;i<x;i++)
#define repn(i,x) for(int i=1;i<=x;i++)
#define SORT(x) sort(x.begin(),x.end())
#define ERASE(x) x.erase(unique(x.begin(),x.end()),x.end())
#define POSL(x,v) (lower_bound(x.begin(),x.end(),v)-x.begin())
#define POSU(x,v) (upper_bound(x.begin(),x.end(),v)-x.begin())
#define all(x) x.begin(),x.end()
#define si(x) int(x.size())

#ifdef LOCAL
#define dmp(x) cerr<<__LINE__<<" "<<#x<<" "<<x<<endl
#else
#define dmp(x) void(0)
#endif

template<class t,class u> bool chmax(t&a,u b){if(a<b){a=b;return true;}else return false;}
template<class t,class u> bool chmin(t&a,u b){if(b<a){a=b;return true;}else return false;}

template<class t> using vc=vector<t>;

template<class t,class u>
ostream& operator<<(ostream& os,const pair<t,u>& p){
	return os<<"{"<<p.fi<<","<<p.sc<<"}";
}

template<class t> ostream& operator<<(ostream& os,const vc<t>& v){
	os<<"{";
	for(auto e:v)os<<e<<",";
	return os<<"}";
}

template<class T>
void g(T &a){
	cin >> a;
}
template<class T>
void o(const T &a,bool space=false){
	cout << a << (space?' ':'\n');
}
//ios::sync_with_stdio(false);
const ll mod = 1000000007;//998244353
mt19937_64 mt(chrono::steady_clock::now().time_since_epoch().count());
template<class T>
void add(T&a,T b){
	a+=b;
	if(a >= mod) a-=mod;
}
ll modpow(ll x,ll n){
	ll res=1;
	while(n>0){
		if(n&1) res=res*x%mod;
		x=x*x%mod;
		n>>=1;
	}
	return res;
}
int n, m, a[105], b[105], k, c[16], d[16];
void solve(){
	cin >> n >> m;
	rep(i, m) cin >> a[i] >> b[i];
	cin >> k;
	rep(i, k) cin >> c[i] >> d[i];
	
	int ans = 0;
	rep(mask, (1<<k)){
		bool ex[105] = {};
		rep(i, k){
			if(((mask>>i)&1)) ex[c[i]] = 1;
			else ex[d[i]] = 1;
		}
		int tmp = 0;
		rep(i, m){
			tmp += ex[a[i]] && ex[b[i]];
		}
		chmax(ans, tmp);
	}
	cout << ans << endl;
}
signed main(){
	cin.tie(0);
	ios::sync_with_stdio(0);
	cout<<fixed<<setprecision(20);
	int t; t = 1; //cin >> t;
	while(t--) solve();
}

#pragma GCC optimize ("O2")
#pragma GCC target ("avx2")
//#include<bits/stdc++.h>
//#include<atcoder/all>
//using namespace atcoder;
#include<iostream>
#include<cstring>

using namespace std;
typedef long long ll;
#define rep(i, n) for(int i = 0; i < (n); i++)
#define rep1(i, n) for(int i = 1; i <= (n); i++)
#define co(x) cout << (x) << "\n"
#define cosp(x) cout << (x) << " "
#define ce(x) cerr << (x) << "\n"
#define cesp(x) cerr << (x) << " "
#define pb push_back
#define mp make_pair
#define chmin(x, y) x = min(x, y)
#define chmax(x, y) x = max(x, y)
#define Would
#define you
#define please

int N;
int to[400001], ne[400001], he[200001];
int Q[200001], vis[200001], p, q;
ll are[200001];

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


	cin >> N;
	rep1(i, N * 2 - 2) {
		int a, b;
		cin >> a >> b;
		to[i] = b;
		ne[i] = he[a];
		he[a] = i++;
		to[i] = a;
		ne[i] = he[b];
		he[b] = i;
	}

	Q[q++] = 1;
	while (p < q) {
		int u = Q[p++];
		vis[u] = -1;
		for (int i = he[u]; i; i = ne[i]) {
			if (vis[to[i]] == 0) {
				Q[q++] = to[i];
			}
		}
	}
	int tmp = Q[N - 1];
	p = 0;
	q = 0;
	Q[q++] = tmp;
	vis[tmp] = 0;
	while (p < q) {
		int u = Q[p++];
		for (int i = he[u]; i; i = ne[i]) {
			if (vis[to[i]] < 0) {
				vis[to[i]] = u;
				Q[q++] = to[i];
			}
		}
	}
	ll m = (1ll << 20) - 1, m0 = ~m, m1 = 1ll << 20;
	for (int i = N - 1; i >= 0; i--) {
		int u = Q[i];
		ll kari = (are[u] & m0) + m1 + u;
		if (are[vis[u]] < kari) are[vis[u]] = kari;
	}

	int k = 0;
	q = 0;
	Q[q++] = tmp;
	while (q) {
		k++;
		int u = Q[q - 1];
		if (u < 0) q--;
		else {
			vis[u] = -k;
			Q[q - 1] = -u;
			int nanika = are[u] & m;
			if(nanika) Q[q++] = nanika;
			for (int i = he[u]; i; i = ne[i]) {
				int v = to[i];
				if (vis[v] >= 0 && v != nanika) {
					Q[q++] = v;
				}
			}
		}
	}

	rep1(i, N) cosp(-vis[i]);

	Would you please return 0;
}