#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 >; 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 SegmentTree { struct node { using result_t = i64; node() : sum(0), lazy(0) {} node(i64 s, int l) : sum(s), lazy(l) {} result_t result() const { return sum; } static node merge(const node& lhs, const node& rhs, int b) { i64 sum = (lhs.sum + rhs.sum) + i64(b) * (lhs.lazy + rhs.lazy); return node(sum, 0); } i64 sum; int lazy; }; SegmentTree(int N) : buff_size(N) { buff = new node[2 * N]; } ~SegmentTree() { delete [] buff; } void propagate(int k) { int ks[30], ki = 0, b = 1; for (k >>= 1; k >= 1; k >>= 1, b <<= 1) ks[ki++] = k; for (; ki; b >>= 1) { int k = ks[--ki]; int l = tree[k].lazy; if (l) { tree[2 * k + 0].lazy += l; tree[2 * k + 1].lazy += l; tree[k].sum += i64(l) * b; tree[k].lazy = 0; } } } void fix(int k, int b) { tree[k] = node::merge(tree[2 * k + 0], tree[2 * k + 1], b >> 1); } void update(int l, int r, int offset=0, int N=0) { size = (N ? N : buff_size); tree = buff + offset * 2; l += size; r += size; propagate(l); propagate(r - 1); int b = 1; bool lup = false, rup = false; for (; l < r; l >>= 1, r >>= 1, b <<= 1) { if (lup) fix(l - 1, b); if (rup) fix(r, b); if (l & 1) tree[l++].lazy += 1, lup = true; if (r & 1) tree[--r].lazy += 1, rup = true; } for (--l; l < r; l >>= 1, r >>= 1, b <<= 1) { if (lup) fix(l, b); if (rup) fix(r, b); } for (; l; l >>= 1, b <<= 1) fix(l, b); } node::result_t query(int l, int r, int offset=0, int N=0) { size = (N ? N : buff_size); tree = buff + offset * 2; l += size; r += size; propagate(l); propagate(r - 1); node left, right; int b = 1; for (; l < r; l >>= 1, r >>= 1, b <<= 1) { if (l & 1) left = node::merge(left, tree[l++], b); if (r & 1) right = node::merge(tree[--r], right, b); } left = node::merge(left, right, b); return left.result(); } 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 = SegmentTree(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.update(l, r, 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.query(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; }