#include <atcoder/all>

#include <bits/stdc++.h>

using namespace std;
#define SZ(x) (int) (x).size()
#define REP(i, n) for(int i = 0; i < (n); i++)
#define FOR(i, a, b) for(auto i = (a); i < (b); i++)
#define For(i, a, b, c) \
	for(auto i = (a); i != (b); i += (c))
#define REPR(i, n) for(auto i = (n) -1; i >= 0; i--)
#define ALL(s) (s).begin(), (s).end()
#define so(V) sort(ALL(V))
#define rev(V) reverse(ALL(V))
#define uni(v) v.erase(unique(ALL(v)), (v).end())
#define eb emplace_back

typedef unsigned long long ull;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<bool> vb;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef pair<int, int> PI;
typedef pair<ll, ll> PL;
const double EPS = 1e-6;
const int MOD = 1e9 + 7;
const int INF = (1 << 30);
const ll LINF = 1e18;
const double math_PI = acos(-1);

template<typename T>
vector<T> make_v(size_t a) {
	return vector<T>(a);
}

template<typename T, typename... Ts>
auto make_v(size_t a, Ts... ts) {
	return vector<decltype(make_v<T>(ts...))>(
		a, make_v<T>(ts...));
}

template<typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(
	T& t, const V& v) {
	t = v;
}

template<typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(
	T& t, const V& v) {
	for(auto& e: t) fill_v(e, v);
}

template<class T>
bool chmax(T& a, const T& b) {
	if(a < b) {
		a = b;
		return true;
	}
	return false;
}

template<class T>
bool chmin(T& a, const T& b) {
	if(a > b) {
		a = b;
		return true;
	}
	return false;
}

template<typename S, typename T>
istream& operator>>(istream& is, pair<S, T>& p) {
	cin >> p.first >> p.second;
	return is;
}

template<typename T>
istream& operator>>(istream& is, vector<T>& vec) {
	for(T& x: vec) is >> x;
	return is;
}

template<typename T>
string join(vector<T>& vec, string splitter) {
	stringstream ss;
	REP(i, SZ(vec)) {
		if(i != 0) ss << splitter;
		ss << vec[i];
	}
	return ss.str();
}

template<typename T>
ostream& operator<<(ostream& os, vector<T>& vec) {
	os << join(vec, " ");
	return os;
}
class HLdecomposition {
private:
	int V;
	vector<vector<int>> G;
	vector<int> stsize, parent, pathtop, in, out;
	int root;
	bool built_flag;
	void BuildStsize(int u, int p) {
		stsize[u] = 1, parent[u] = p;
		for(int& v: G[u]) {
			if(v == p) {
				if(v == G[u].back())
					break;
				else
					swap(v, G[u].back());
			}
			BuildStsize(v, u);
			stsize[u] += stsize[v];
			if(stsize[v] > stsize[G[u][0]]) {
				swap(v, G[u][0]);
			}
		}
	}
	void BuildPath(int u, int p, int& tm) {
		in[u] = tm++;
		for(int v: G[u]) {
			if(v == p) continue;
			pathtop[v] = (v == G[u][0] ? pathtop[u] : v);
			BuildPath(v, u, tm);
		}
		out[u] = tm;
	}

public:
	void add_edge(int u, int v) {
		G[u].push_back(v), G[v].push_back(u);
	}
	void build(int _root = 0) {
		root = _root;
		built_flag = true;
		int tm = 0;
		BuildStsize(root, -1);
		pathtop[root] = root;
		BuildPath(root, -1, tm);
	}
	//蜈・・鬆らせ縺ｮ繧､繝ｳ繝・ャ繧ｯ繧ｹ縺ｮ驟榊・荳翫〒縺ｮid繧定ｿ斐☆
	inline int get(int a) {
		return in[a];
	}
	int lca(int a, int b) {
		int pa = pathtop[a], pb = pathtop[b];
		while(pathtop[a] != pathtop[b]) {
			if(in[pa] > in[pb]) {
				a = parent[pa], pa = pathtop[a];
			} else {
				b = parent[pb], pb = pathtop[b];
			}
		}
		if(in[a] > in[b]) swap(a, b);
		return a;
	}
	void subtree_query(
		int a, const function<void(int, int)>& func) {
		assert(
			built_flag
			&& "You must call hld.build() before call query function");
		func(in[a], out[a]);
	}
	// 萓・ hl.path_query(q, r, [&](int l, int r){ seg.range(l, r, s); })
	void path_query(int a, int b,
					const function<void(int, int)>& func) {
		assert(
			built_flag
			&& "You must call hld.build() before call query function");
		int pa = pathtop[a], pb = pathtop[b];
		while(pathtop[a] != pathtop[b]) {
			if(in[pa] > in[pb]) {
				func(in[pa], in[a] + 1);
				a = parent[pa], pa = pathtop[a];
			} else {
				func(in[pb], in[b] + 1);
				b = parent[pb], pb = pathtop[b];
			}
		}
		if(in[a] > in[b]) swap(a, b);
		func(in[a], in[b] + 1);
	}
	HLdecomposition(int node_size)
		: V(node_size),
		  G(V),
		  stsize(V, 0),
		  parent(V, -1),
		  pathtop(V, -1),
		  in(V, -1),
		  out(V, -1),
		  built_flag(false) {
	}
};
using namespace atcoder;
struct S {
	ll value;
	int size;
};
using F = ll;

S op(S a, S b) {
	return { a.value + b.value, a.size + b.size };
}
S e() {
	return { 0, 0 };
}
S mapping(F f, S x) {
	return { x.value + f * x.size, x.size };
}
F composition(F f, F g) {
	return f + g;
}
F id() {
	return 0;
}

int main() {
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	int N;
	cin >> N;
	HLdecomposition hld(N);
	REP(i, N - 1) {
		int u, v;
		cin >> u >> v;
		u--;
		v--;
		hld.add_edge(u, v);
	}
	hld.build();
	int Q;
	cin >> Q;
	lazy_segtree<S, op, e, F, mapping, composition, id> seg(
		vector<S>(N, { 1, 1 }));
	ll ans = 0;
	REP(q, Q) {
		int A, B;
		cin >> A >> B;
		A--;
		B--;
		hld.path_query(A, B, [&](int l, int r) {
			ans += seg.prod(l, r).value;
			seg.apply(l, r, 1);
		});
	}
	cout << ans << endl;
	return 0;
}