#define _USE_MATH_DEFINES #include using namespace std; class LowestCommonAncestor { private: static const int MAX_SIZE = 30; vector> graph; vector parent[MAX_SIZE]; vector depth; int bit_length; void copy(const vector g[], int siz) { graph.resize(siz); for (int i = 0; i < siz; ++i) for (int j : g[i]) graph[i].push_back(j); } void copy(const vector>& g, int siz = -1) { if (siz < 0) siz = (int) g.size(); graph.resize(siz); for (int i = 0; i < siz; ++i) for (int j : g[i]) graph[i].push_back(j); } void initialize() { int siz = (int) graph.size(); int root = 0; bit_length = 1; while ((1 << bit_length) < siz) ++bit_length; for (int i = 0; i < bit_length; ++i) parent[i].resize(siz); depth.assign(siz, -1); dfs(root, -1, 0); for (int i = 0; i < bit_length- 1; ++i) { for (int v = 0; v < siz; ++v) { if (depth[v] == -1) continue; if (parent[i][v] < 0) parent[i + 1][v] = -1; else parent[i + 1][v] = parent[i][parent[i][v]]; } } } void dfs(int cur, int par, int d) { parent[0][cur] = par; depth[cur] = d; for (int child : graph[cur]) if (child != par) dfs(child, cur, d + 1); } public: LowestCommonAncestor() {} LowestCommonAncestor(const vector>& g, int siz = -1) { build(g, siz); } LowestCommonAncestor(const vector g[], int siz) { build(g, siz); } void build(const vector g[], int siz) { copy(g, siz); initialize(); } void build(const vector>& g, int siz = -1) { copy(g, siz); initialize(); } int get(int u, int v) { if (depth[u] > depth[v]) swap(u, v); for (int i = 0; i < bit_length; ++i) if (((depth[v] - depth[u]) >> i) & 1) v = parent[i][v]; if (u == v) return u; for (int i = bit_length - 1; i >= 0; --i) if (parent[i][u] != parent[i][v]) u = parent[i][u], v = parent[i][v]; return parent[0][u]; } }; using LCA = LowestCommonAncestor; vector> g[101010]; vector gg[101010]; long long dist[101010]; void dfs (int cur, int par, long long d) { dist[cur] = d; for (auto p : g[cur]) { if (p.first == par) continue; dfs(p.first, cur, d + p.second); } } signed main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin >> n; for (int i = 0; i + 1 < n; i++) { int u, v, w; cin >> u >> v >> w; g[u].emplace_back(v, w); g[v].emplace_back(u, w); gg[u].push_back(v); gg[v].push_back(u); } LCA lca(gg, n); dfs (0, -1, 0); int q; cin >> q; while (q--) { int x, y, z; cin >> x >> y >> z; cout << (dist[x] * 2 + dist[y] * 2 + dist[z] * 2 - dist[lca.get(x, y)] * 2 - dist[lca.get(y, z)] * 2 - dist[lca.get(z, x)] * 2) / 2 << '\n'; } return 0; }