#pragma GCC optimize ("O3") #pragma GCC target ("avx") // #pragma GCC target ("sse4") // SPOJ, codechef #include #include #include #include #include #include #include #include #include #include #include #include #define _rep(_1, _2, _3, _4, name, ...) name #define rep2(i, n) rep3(i, 0, n) #define rep3(i, a, b) rep4(i, a, b, 1) #define rep4(i, a, b, c) for (int i = int(a); i < int(b); i += int(c)) #define rep(...) _rep(__VA_ARGS__, rep4, rep3, rep2, _)(__VA_ARGS__) using namespace std; using i64 = long long; using u8 = unsigned char; using u32 = unsigned; using u64 = unsigned long long; using f80 = long double; using Edges = vector< vector >; // ref. pekempey さん struct HLD { struct node { int id, par, head; }; HLD(const Edges& edges) : N(edges.size()), edges(edges), tree(N) { dfs(); path(); } int dfs(int v=0, int p=-1) { int cnt = 1, x = 0, h = -1; for (auto w : edges[v]) if (w != p) { tree[w].par = v; int c = dfs(w, v); if (c > x) x = c, h = w; cnt += c; } tree[v].head = h; return cnt; } void path() { int id = 0; tree[id].par = -1; queue que; que.push(id); while (!que.empty()) { int len = 0, v = que.front(); que.pop(); for (int w = v, h = -1; w >= 0; w = h, ++len) { tree[w].id = id++; h = tree[w].head; tree[w].head = v; for (auto x : edges[w]) if (x != h && x != tree[w].par) que.push(x); } tree[v].head = -len; } } int head(int v) const { return tree[v].head < 0 ? v : tree[v].head; } template void update(int v, int w, func_t func) { while (1) { if (tree[v].id < tree[w].id) swap(v, w); int hv = head(v), ofs = tree[hv].id, size = -tree[hv].head; if (hv != head(w)) { func(0, tree[v].id - ofs + 1, ofs, size); v = tree[hv].par; continue; } func(tree[w].id - ofs, tree[v].id - ofs + 1, ofs, size); break; } } int N; const Edges& edges; vector tree; }; Edges edges; struct FenwickTree { struct node { node() : d0(0), d1(0) {} i64 d0, d1; }; FenwickTree(int n) : buff_size(2 * n) { buff = new node[buff_size]; rep(i, buff_size) buff[i] = node(); } ~FenwickTree() { delete [] buff; } void reset(int o, int s) { size = s; tree = buff + o * 2; } void add(int l, i64 v0, i64 v1) { for (; l <= size; l += l & -l) { tree[l].d0 += v0; tree[l].d1 += v1; } } void add(int l, int r, int v, int o, int s) { reset(o, s); add(l + 1, i64(-v) * l, v); add(r + 1, i64(v) * r, -v); } i64 sum(int l) { int ll = l; i64 r0 = 0, r1 = 0; for (; l; l &= l - 1) { r0 += tree[l].d0; r1 += tree[l].d1; } return r0 + ll * r1; } i64 sum(int l, int r, int o, int s) { reset(o, s); return sum(r) - sum(l); } int buff_size; node* buff; int size; node* tree; }; void solve() { int N; while (~scanf("%d", &N)) { edges.clear(); edges.resize(N); rep(i, N) edges[i].reserve(8); rep(i, N - 1) { int v, w; scanf("%d %d", &v, &w); --v; --w; edges[v].push_back(w); edges[w].push_back(v); } auto hld = HLD(edges); auto tree = FenwickTree(N); int Q; scanf("%d", &Q); rep(i, Q) { int v, w; scanf("%d %d", &v, &w); --v, --w; hld.update(v, w, [&](int l, int r, int o, int s) { tree.add(l, r, 1, o, s); }); } auto tri = [](int n) { return i64(n) * (n + 1) / 2; }; i64 ans = 0; rep(i, N) if (hld.tree[i].head < 0) { int o = hld.tree[i].id; int l = -hld.tree[i].head; rep(j, l) ans += tri(tree.sum(j, j + 1, o, l)); } printf("%lld\n", ans); } } int main() { clock_t beg = clock(); solve(); clock_t end = clock(); fprintf(stderr, "%.3f sec\n", double(end - beg) / CLOCKS_PER_SEC); return 0; }