// includes #include // macros #define pb emplace_back #define mk make_pair #define pq priority_queue #define FOR(i, a, b) for(int i=(a);i<(b);++i) #define rep(i, n) FOR(i, 0, n) #define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--) #define irep(itr, st) for(auto itr = (st).begin(); itr != (st).end(); ++itr) #define irrep(itr, st) for(auto itr = (st).rbegin(); itr != (st).rend(); ++itr) #define vrep(v, i) for(int i = 0; i < (v).size(); i++) #define all(x) (x).begin(),(x).end() #define sz(x) ((int)(x).size()) #define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end()) #define FI first #define SE second #define bit(n) (1LL<<(n)) #define INT(n) int n; cin >> n; #define LL(n) ll n; cin >> n; #define DOUBLE(n) double n; cin >> n; using namespace std; template bool chmax(T &a, const T &b){if(a < b){a = b; return 1;} return 0;} template bool chmin(T &a, const T &b){if(a > b){a = b; return 1;} return 0;} template istream &operator>>(istream &is, vector &vec){for(auto &v: vec)is >> v; return is;} template ostream &operator<<(ostream &os, const vector& vec){for(int i = 0; i < vec.size(); i++){ os << vec[i]; if(i + 1 != vec.size())os << " ";} return os;} template ostream &operator<<(ostream &os, const set& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const unordered_set& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const multiset& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const unordered_multiset& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const pair &p){os << p.first << " " << p.second; return os;} template ostream &operator<<(ostream &os, const map &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;} template ostream &operator<<(ostream &os, const unordered_map &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;} // types using ll = long long int; using P = pair; using Pli = pair; using Pil = pair; using Pll = pair; using Pdd = pair; using cd = complex; // constants const int inf = 1e9; const ll linf = 1LL << 50; const double EPS = 1e-10; const int mod = 1e9 + 7; const int dx[4] = {-1, 0, 1, 0}; const int dy[4] = {0, -1, 0, 1}; // solve vector child[100010]; struct Tree2{ int n = 0, m = 0; vector> edge; vector> par; vector vis; vector h; Tree2(){} Tree2(int n): n(n){ while((1LL<(n, 0)); vis.resize(n, false); h.resize(n); } void adde(int from, int to){ edge[from].emplace_back(to); } void dfs(int i){ vis[i] = true; for(auto e: edge[i]){ if(!vis[e]){ par[0][e] = i; h[e] = h[i] + 1; child[i].pb(e); dfs(e); } } } void build(){ fill(vis.begin(), vis.end(), false); fill(h.begin(), h.end(), 0); par[0][0] = 0; h[0] = 0; dfs(0); for(int i = 1; i <= m; i++){ for(int j = 0; j < n; j++){ par[i][j] = par[i-1][par[i-1][j]]; } } } int go_up(int u, int k){ int i = 0; while(k){ if(k % 2 == 1){ u = par[i][u]; } i++; k /= 2; } return u; } int lca(int u, int v){ if(h[u] > h[v])u = go_up(u, h[u] - h[v]); if(h[u] < h[v])v = go_up(v, h[v] - h[u]); if(u == v)return u; int ld = 0, rd = n; while(rd - ld > 1){ int k = (rd + ld) / 2; int uk = go_up(u, k); int vk = go_up(v, k); if(uk == vk)rd = k; else ld = k; } return go_up(u, rd); } }; ll sum[100010]; void calc(int i){ for(auto e: child[i]){ calc(e); sum[i] += sum[e]; } } int main(int argc, char const* argv[]) { ios_base::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(20); INT(n); Tree2 t2(n); rep(i, n - 1){ INT(u); INT(v); u--; v--; t2.adde(u, v); t2.adde(v, u); } t2.build(); INT(q); rep(i, q){ INT(a); INT(b); a--; b--; sum[a]++; sum[b]++; int l = t2.lca(a, b); sum[l]--; if(l != 0)sum[t2.par[0][l]]--; } calc(0); ll res = 0; rep(i, n){ res += (sum[i] + 1) * sum[i] / 2; } cout << res << endl; return 0; }