#include <bits/stdc++.h>
using namespace std;
using lint = long long;
template<class T = int> using V = vector<T>;
template<class T = int> using VV = V< V<T> >;

template<class T> struct FenwickTree {
  const int n;
  V<T> t;
  FenwickTree(int n) : n(n), t(n + 1) {}
  void add(int i, T x) { for (++i; i <= n; i += i & -i) t[i] += x; }
  T sum(int i) const {
    T s = 0;
    for (; i; i -= i & -i) s += t[i];
    return s;
  }
};
template<class T> struct AddSumTree {
  const int n;
  FenwickTree<T> d, e;
  AddSumTree(int n) : n(n), d(n), e(n) {}
  void add(int l, int r, T x) {
    d.add(l, x), e.add(l, l * x);
    if (r < n) d.add(r, -x), e.add(r, -r * x);
  }
  T sum(int i) const { return i * d.sum(i) - e.sum(i); }
  T sum(int l, int r) const { return sum(r) - sum(l); }
};
using Tree = AddSumTree<uint64_t>;

struct HeavyLightDecomposition {
  const bool edge;
  const int n;
  VV<> g;
  V<> sz, par, in, out, anc, rev;
  HeavyLightDecomposition(VV<>& g, bool edge, int r = 0) :
    edge(edge), n(g.size()), g(g), sz(n), par(n), in(n), out(n), anc(n), rev(n) {
    dfs_sz(r, -1);
    anc[r] = r;
    dfs_hl(r);
  }
  void dfs_sz(int v, int p) {
    par[v] = p;
    for (auto&& w : g[v]) if (w == p) {
      swap(w, g[v].back());
      g[v].pop_back();
      break;
    }
    sz[v] = 1;
    for (auto&& w : g[v]) {
      dfs_sz(w, v);
      sz[v] += sz[w];
      if (sz[w] > sz[g[v][0]]) swap(w, g[v][0]);
    }
  }
  void dfs_hl(int v) {
    static int t = 0;
    in[v] = t++;
    rev[in[v]] = v;
    for (int w : g[v]) {
      anc[w] = w == g[v][0] ? anc[v] : w;
      dfs_hl(w);
    }
    out[v] = t;
  }
  int lca(int u, int v) const {
    while (true) {
      if (in[u] > in[v]) swap(u, v);
      if (anc[u] == anc[v]) return u;
      v = par[anc[v]];
    }
  }
  lint acc(Tree& t, int u, int v) const {
    lint res = 0;
    while (true) {
      if (in[u] > in[v]) swap(u, v);
      if (anc[u] == anc[v]) break;
      res += t.sum(in[anc[v]], in[v] + 1);
      v = par[anc[v]];
    }
    res += t.sum(in[u] + edge, in[v] + 1);
    return res;
  }
  void act(Tree& t, int u, int v, int f) const {
    while (true) {
      if (in[u] > in[v]) swap(u, v);
      if (anc[u] == anc[v]) break;
      t.add(in[anc[v]], in[v] + 1, f);
      v = par[anc[v]];
    }
    t.add(in[u] + edge, in[v] + 1, f);
  }
};

int main() {
  cin.tie(nullptr); ios::sync_with_stdio(false);
  int n; cin >> n;
  VV<> g(n);
  for (int i = 0; i < n - 1; ++i) {
    int u, v; cin >> u >> v, --u, --v;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  HeavyLightDecomposition hld(g, false);
  Tree t(n);
  t.add(0, n, 1);
  int q; cin >> q;
  lint res = 0;
  while (q--) {
    int u, v; cin >> u >> v, --u, --v;
    res += hld.acc(t, u, v);
    hld.act(t, u, v, 1);
  }
  cout << res << '\n';
}