#include using namespace std; using ll = long long; using ld = long double; template using V = vector; using VI = V; using VL = V; using VS = V; template using PQ = priority_queue, greater>; using graph = V; template using w_graph = V>>; #define FOR(i,a,n) for(int i=(a);i<(n);++i) #define eFOR(i,a,n) for(int i=(a);i<=(n);++i) #define rFOR(i,a,n) for(int i=(n)-1;i>=(a);--i) #define erFOR(i,a,n) for(int i=(n);i>=(a);--i) #define all(a) a.begin(),a.end() #define rall(a) a.rbegin(),a.rend() #define inside(h,w,y,x) (unsigned(y) inline bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; }return false; } template inline bool chmin(T& a, const T& b) { if (a > b) { a = b; return true; }return false; } inline void init() { cin.tie(nullptr); cout.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } template inline istream& operator>>(istream& is, V& v) { for (auto& a : v)is >> a; return is; } template inline istream& operator>>(istream& is, pair& p) { is >> p.first >> p.second; return is; } template inline V vec(size_t a) { return V(a); } template inline V defvec(T def, size_t a) { return V(a, def); } template inline auto vec(size_t a, Ts... ts) { return V(ts...))>(a, vec(ts...)); } template inline auto defvec(T def, size_t a, Ts... ts) { return V(def, ts...))>(a, defvec(def, ts...)); } template inline void print(const T& a) { cout << a << "\n"; } template inline void print(const T& a, const Ts&... ts) { cout << a << " "; print(ts...); } template inline void print(const V& v) { for (int i = 0; i < v.size(); ++i)cout << v[i] << (i == v.size() - 1 ? "\n" : " "); } template inline void print(const V>& v) { for (auto& a : v)print(a); } template inline constexpr const T& cumsum(const V& a, int l, int r) { return 0 <= l && l <= r && r < a.size() ? a[r] - (l == 0 ? 0 : a[l - 1]) : 0; }//[l,r] template inline constexpr const T& min(const V& v) { return *min_element(all(v)); } template inline constexpr const T& max(const V& v) { return *max_element(all(v)); } int main() { init(); int n; cin >> n; w_graph g(n); FOR(i, 0, n - 1) { int a, b, c; cin >> a >> b >> c; --a, --b; g[a].emplace_back(b, c); g[b].emplace_back(a, c); } VI x(n), siz(n, 1); auto setup_dfs = [&](auto&& f, int cur, int par)->void { for (auto [to, weight] : g[cur]) { if (to == par)continue; x[to] = x[cur] ^ weight; f(f, to, cur); siz[cur] += siz[to]; } }; setup_dfs(setup_dfs, 0, -1); auto sorted_x = x; sort(sorted_x.begin(), sorted_x.end()); sorted_x.erase(unique(sorted_x.begin(), sorted_x.end()), sorted_x.end()); FOR(i, 0, n)x[i] = lower_bound(sorted_x.begin(), sorted_x.end(), x[i]) - sorted_x.begin();//compress ll ans = ll(n) * (n - 1); VI cnt(n), y(n); auto calc_dfs = [&](auto&& f, int cur, int par)->void { ans -= y[x[cur]]; ans -= ll(siz[cur]) * cnt[x[cur]]; for (auto [to, weight] : g[cur]) { if (to == par)continue; int tmp_cnt = cnt[x[cur]], tmp_y = y[x[cur]]; cnt[x[cur]] = 1, y[x[cur]] = n - siz[to]; f(f, to, cur); cnt[x[cur]] = tmp_cnt, y[x[cur]] = tmp_y; } y[x[cur]] += siz[cur]; ++cnt[x[cur]]; }; calc_dfs(calc_dfs, 0, -1); print(ans); return 0; }