#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
template<class T> using V = vector<T>;
using VI = V<int>;
using VL = V<ll>;
using VS = V<string>;
template<class T> using PQ = priority_queue<T, V<T>, greater<T>>;
using graph = V<VI>;
template<class T> using w_graph = V<V<pair<int, T>>>;
#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)<h&&unsigned(x)<w)
#ifdef _DEBUG
#define line cout << "-----------------------------\n"
#define stop system("pause")
#endif
constexpr ll INF = 1000000000;
constexpr ll LLINF = 1LL << 61;
constexpr ll mod = 1000000007;
constexpr ll MOD = 998244353;
constexpr ld eps = 1e-10;
constexpr int dy[]{ -1,0,1,0 }, dx[]{ 0,1,0,-1 };
template<class T> inline bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; }return false; }
template<class T> 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<class T> inline istream& operator>>(istream& is, V<T>& v) { for (auto& a : v)is >> a; return is; }
template<class T, class U> inline istream& operator>>(istream& is, pair<T, U>& p) { is >> p.first >> p.second; return is; }
template<class T> inline V<T> vec(size_t a) { return V<T>(a); }
template<class T> inline V<T> defvec(T def, size_t a) { return V<T>(a, def); }
template<class T, class... Ts> inline auto vec(size_t a, Ts... ts) { return V<decltype(vec<T>(ts...))>(a, vec<T>(ts...)); }
template<class T, class... Ts> inline auto defvec(T def, size_t a, Ts... ts) { return V<decltype(defvec<T>(def, ts...))>(a, defvec<T>(def, ts...)); }
template<class T> inline void print(const T& a) { cout << a << "\n"; }
template<class T, class... Ts> inline void print(const T& a, const Ts&... ts) { cout << a << " "; print(ts...); }
template<class T> inline void print(const V<T>& v) { for (int i = 0; i < v.size(); ++i)cout << v[i] << (i == v.size() - 1 ? "\n" : " "); }
template<class T> inline void print(const V<V<T>>& v) { for (auto& a : v)print(a); }
template<class T> inline constexpr const T& cumsum(const V<T>& 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<class T> inline constexpr const T& min(const V<T>& v) { return *min_element(all(v)); }
template<class T> inline constexpr const T& max(const V<T>& v) { return *max_element(all(v)); }

int main() {
    init();

    int n; cin >> n;
    w_graph<int> 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;
}