// need #include #include // data structure #include #include #include #include #include #include #include #include #include //#include #include #include #include #include // etc #include #include #include #include #include #include #include // input #define INIT std::ios::sync_with_stdio(false);std::cin.tie(0); #define VAR(type, ...)type __VA_ARGS__;MACRO_VAR_Scan(__VA_ARGS__); template void MACRO_VAR_Scan(T& t) { std::cin >> t; } templatevoid MACRO_VAR_Scan(First& first, Rest& ...rest) { std::cin >> first; MACRO_VAR_Scan(rest...); } #define VEC_ROW(type, n, ...)std::vector __VA_ARGS__;MACRO_VEC_ROW_Init(n, __VA_ARGS__); for(int w_=0; w_ void MACRO_VEC_ROW_Init(int n, T& t) { t.resize(n); } templatevoid MACRO_VEC_ROW_Init(int n, First& first, Rest& ...rest) { first.resize(n); MACRO_VEC_ROW_Init(n, rest...); } template void MACRO_VEC_ROW_Scan(int p, T& t) { std::cin >> t[p]; } templatevoid MACRO_VEC_ROW_Scan(int p, First& first, Rest& ...rest) { std::cin >> first[p]; MACRO_VEC_ROW_Scan(p, rest...); } #define VEC(type, c, n) std::vector c(n);for(auto& i:c)std::cin>>i; #define MAT(type, c, m, n) std::vector> c(m, std::vector(n));for(auto& R:c)for(auto& w:R)std::cin>>w; // output #define OUT(dist) std::cout<<(dist); #define FOUT(n, dist) std::cout<=(a);--w) #define REP(w, n) for(int w=0;w=0;--w) #define IN(a, x, b) (a<=x && x inline T CHMAX(T & a, const T b) { return a = (a < b) ? b : a; } template inline T CHMIN(T& a, const T b) { return a = (a > b) ? b : a; } // test template using V = std::vector; template using VV = V>; template std::ostream& operator<<(std::ostream& os, std::pair p) { os << "(" << p.first << ", " << p.second << ")"; return os; } // type/const #define int ll using ll = long long; using ull = unsigned long long; using ld = long double; using PAIR = std::pair; using PAIRLL = std::pair; constexpr int INFINT = (1 << 30) - 1; // 1.07x10^ 9 constexpr int INFINT_LIM = (1LL << 31) - 1; // 2.15x10^ 9 constexpr ll INFLL = 1LL << 60; // 1.15x10^18 constexpr ll INFLL_LIM = (1LL << 62) - 1 + (1LL << 62); // 9.22x10^18 constexpr double EPS = 1e-10; constexpr int MOD = 1000000007; constexpr double PI = 3.141592653589793238462643383279; template void FILL(T(&a)[N], const T & val) { for (auto& x : a) x = val; } template void FILL(ARY(&a)[N][M], const T & val) { for (auto& b : a) FILL(b, val); } template void FILL(std::vector & a, const T & val) { for (auto& x : a) x = val; } template void FILL(std::vector> & a, const T & val) { for (auto& b : a) FILL(b, val); } // ------------>8------------------------------------->8------------ // write [ LCA lca(g, root); ] when using this snippet. class LCA { private: const std::vector>& graph; // graph's list expression int root; int n; // the number of nodes int log2n; // = floor(log2(n)) + 1 std::vector> parent; // parent[x][v] = a parent(above 2^x) of v (nonexistence -> -1) std::vector depth; // the depth of each node public: LCA(const std::vector>& graph, int root) : graph(graph), root(root), n(graph.size()), log2n(std::floor(std::log2(n) + 1)), parent(log2n, std::vector(n, 0)), depth(n, 0) { init(); } // Check the depth of each node(node "v" -> parent is "p", depth is "d") void dfs(int v, int p, int d) { std::stack stack; stack.push(v); parent[0][v] = p; depth[v] = d; while (!stack.empty()) { int now = stack.top(); stack.pop(); for (int i = 0; i < graph[now].size(); ++i) { int to = graph[now][i]; if (to == parent[0][now]) continue; parent[0][to] = now; depth[to] = depth[now] + 1; stack.push(to); // Check each child of v } } } // Initialize void init() { // Initialize "parent[0]" and "depth" dfs(root, -1, 0); // Initialize "parent" for (int k = 0; k < log2n - 1; ++k) { for (int v = 0; v < n; ++v) { if (parent[k][v] < 0) { // If parent above 2^k of v is nonexistence parent[k + 1][v] = -1; } else { parent[k + 1][v] = parent[k][parent[k][v]]; } } } } // Find LCA of (u, v) int lca(int u, int v) { // go up parent while depth of u and v is same if (depth[u] > depth[v]) std::swap(u, v); for (int k = 0; k < log2n; ++k) { if ((depth[v] - depth[u]) >> k & 1) { v = parent[k][v]; // go up to 2^k if k-th binary is 1 } } if (u == v) return u; // this case is that v is in u's subtree // Find LCA by binary searching for (int k = log2n - 1; k >= 0; --k) { if (parent[k][u] != parent[k][v]) { u = parent[k][u]; v = parent[k][v]; } } return parent[0][u]; } }; signed main() { INIT; VAR(int, n); VEC_ROW(int, n - 1, a, b, c); std::vector> g(n); std::vector> g_(n); REP(i, n-1) { g[a[i]].emplace_back(b[i], c[i]); g[b[i]].emplace_back(a[i], c[i]); g_[a[i]].emplace_back(b[i]); g_[b[i]].emplace_back(a[i]); } V dist(n, INFLL); dist[0] = 0; { auto rec = [&](auto && f, int v, int par) -> void { for (auto& e : g[v]) if (e.first != par) { dist[e.first] = dist[v] + e.second; f(f, e.first, v); } }; rec(rec, 0, -1); } VAR(int, Q); LCA lca(g_, 0); REP(_, Q) { VAR(int, x, y, z); int ans = INFLL; REP(i1, 3) { int w = lca.lca(x, y); int v = lca.lca(w, z); CHMIN(ans, dist[x] + dist[y] - dist[w] + dist[z] - 2 * dist[v]); int t; t = x; x = y; y = z; z = t; } OUT(ans)BR; } return 0; }