#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < n; i++)
#define rep2(i, x, n) for (int i = x; i <= n; i++)
#define rep3(i, x, n) for (int i = x; i >= n; i--)
#define each(e, v) for (auto &e : v)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
using ll = long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;

template <typename T>
bool chmax(T &x, const T &y) {
    return (x < y) ? (x = y, true) : false;
}

template <typename T>
bool chmin(T &x, const T &y) {
    return (x > y) ? (x = y, true) : false;
}

template <typename T>
int flg(T x, int i) {
    return (x >> i) & 1;
}

template <typename T>
void print(const vector<T> &v, T x = 0) {
    int n = v.size();
    for (int i = 0; i < n; i++) cout << v[i] + x << (i == n - 1 ? '\n' : ' ');
    if (v.empty()) cout << '\n';
}

template <typename T>
void printn(const vector<T> &v, T x = 0) {
    int n = v.size();
    for (int i = 0; i < n; i++) cout << v[i] + x << '\n';
}

template <typename T>
int lb(const vector<T> &v, T x) {
    return lower_bound(begin(v), end(v), x) - begin(v);
}

template <typename T>
int ub(const vector<T> &v, T x) {
    return upper_bound(begin(v), end(v), x) - begin(v);
}

template <typename T>
void rearrange(vector<T> &v) {
    sort(begin(v), end(v));
    v.erase(unique(begin(v), end(v)), end(v));
}

template <typename T>
vector<int> id_sort(const vector<T> &v, bool greater = false) {
    int n = v.size();
    vector<int> ret(n);
    iota(begin(ret), end(ret), 0);
    sort(begin(ret), end(ret), [&](int i, int j) { return greater ? v[i] > v[j] : v[i] < v[j]; });
    return ret;
}

template <typename S, typename T>
pair<S, T> operator+(const pair<S, T> &p, const pair<S, T> &q) {
    return make_pair(p.first + q.first, p.second + q.second);
}

template <typename S, typename T>
pair<S, T> operator-(const pair<S, T> &p, const pair<S, T> &q) {
    return make_pair(p.first - q.first, p.second - q.second);
}

template <typename S, typename T>
istream &operator>>(istream &is, pair<S, T> &p) {
    S a;
    T b;
    is >> a >> b;
    p = make_pair(a, b);
    return is;
}

template <typename S, typename T>
ostream &operator<<(ostream &os, const pair<S, T> &p) {
    return os << p.first << ' ' << p.second;
}

struct io_setup {
    io_setup() {
        ios_base::sync_with_stdio(false);
        cin.tie(NULL);
        cout << fixed << setprecision(15);
    }
} io_setup;

const int inf = (1 << 30) - 1;
const ll INF = (1LL << 60) - 1;
const int MOD = 1000000007;
// const int MOD = 998244353;

template <typename T, bool directed = false>
struct Weighted_Graph {
    struct edge {
        int to, id;
        T cost;
        edge(int to, int id, T cost) : to(to), id(id), cost(cost) {}
    };

    vector<vector<edge>> es;
    const int n;
    int m;

    vector<int> si;
    vector<bool> used;
    vector<int> col;

    Weighted_Graph(int n) : es(n), n(n), m(0), si(n), used(n, false), col(n, 0) {}

    void add_edge(int from, int to, T cost) {
        es[from].emplace_back(to, m, cost);
        if (!directed) es[to].emplace_back(from, m, cost);
        m++;
    }

    int calc_size(int now, int pre = -1) {
        si[now] = 1;
        for (auto &e : es[now]) {
            if (e.to == pre || used[e.to]) continue;
            si[now] += calc_size(e.to, now);
        }
        return si[now];
    }

    pair<int, int> search_centroid(int now, int sz, int pre = -1) { // (残りの最大部分木の頂点数、重心)
        pair<int, int> ret = make_pair(INT_MAX, -1);
        int M = 0, S = 1;
        for (auto &e : es[now]) {
            if (e.to == pre || used[e.to]) continue;
            ret = min(ret, search_centroid(e.to, sz, now));
            M = max(M, si[e.to]);
            S += si[e.to];
        }
        M = max(M, sz - S);
        ret = min(ret, make_pair(M, now));
        return ret;
    }

    int centroid(int s) { // 頂点sを含む連結成分の重心を返す
        calc_size(s);
        return search_centroid(s, si[s]).second;
    }

    void dfs1(int now, int pre = -1) {
        each(e, es[now]) {
            if (e.to == pre) continue;
            col[e.to] = col[now] ^ e.cost;
            dfs1(e.to, now);
        }
    }

    vector<int> cnt1_all, cnt2_all, cnt1_tmp, cnt2_tmp;
    vector<int> cnt;

    void compress() {
        dfs1(0);
        vector<int> xs = col;
        rearrange(xs);
        rep(i, n) col[i] = lb(xs, col[i]);
        int K = sz(xs);
        cnt1_all.assign(K, 0), cnt2_all.assign(K, 0);
        cnt1_tmp.assign(K, 0), cnt2_tmp.assign(K, 0);
        cnt.assign(K, 0);
    }

    vector<int> cols_all, cols_tmp;

    int dfs2(int now, int pre = -1) {
        int ret = 1;
        if (cnt[col[now]]++ == 0) cnt1_tmp[col[now]]++;
        each(e, es[now]) {
            if (e.to == pre || used[e.to]) continue;
            ret += dfs2(e.to, now);
        }
        if (--cnt[col[now]] == 0) cnt2_tmp[col[now]] -= ret;
        cols_tmp.eb(col[now]);
        return ret;
    }

    ll decompose(int root = 0) {
        ll ret = 0;
        int c = centroid(root);
        used[c] = true;
        int s = 1;
        each(e, es[c]) {
            if (used[e.to]) continue;
            int x = dfs2(e.to);
            s += x;
            // cout << c << ' ' << e.to << '\n';
            // print(cnt1_tmp), print(cnt2_tmp), print(cnt);
            each(i, cols_tmp) {
                if (cnt[i]++ == 0) {
                    if (i != col[c]) ret -= 1LL * cnt1_tmp[i] * (x + cnt2_tmp[i]);
                    cnt1_all[i] += cnt1_tmp[i];
                    cnt2_all[i] += cnt2_tmp[i];
                    cnt1_tmp[i] = 0;
                    cnt2_tmp[i] = 0;
                    cols_all.eb(i);
                }
            }
            each(i, cols_tmp) cnt[i] = 0;
            cols_tmp.clear();
        }
        ret += s - 1 + cnt2_all[col[c]];
        each(i, cols_all) {
            if (cnt[i]++ == 0) {
                if (i != col[c]) ret += 1LL * cnt1_all[i] * (s + cnt2_all[i]);
                cnt1_all[i] = 0;
                cnt2_all[i] = 0;
            }
        }
        each(i, cols_all) cnt[i] = 0;
        cols_all.clear();
        // cout << c << ' ' << ret << '\n';

        for (auto &e : es[c]) {
            if (!used[e.to]) ret += decompose(e.to);
        }
        return ret;
    }

    void solve() {
        compress();
        cout << decompose() << '\n';
    }
};

int main() {
    int N;
    cin >> N;

    Weighted_Graph<int> G(N);
    rep(i, N - 1) {
        int u, v, c;
        cin >> u >> v >> c;
        u--, v--;
        G.add_edge(u, v, c);
    }

    G.solve();
}