/*
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
//*/

#include <bits/stdc++.h>

// #include <atcoder/all>
// #include <atcoder/maxflow>

using namespace std;
// using namespace atcoder;

#define DEBUG(x) cerr << #x << ": " << x << endl;
#define DEBUG_VEC(v)                                        \
    cerr << #v << ":";                                      \
    for (int iiiiiiii = 0; iiiiiiii < v.size(); iiiiiiii++) \
        cerr << " " << v[iiiiiiii];                         \
    cerr << endl;
#define DEBUG_MAT(v)                                \
    cerr << #v << endl;                             \
    for (int iv = 0; iv < v.size(); iv++) {         \
        for (int jv = 0; jv < v[iv].size(); jv++) { \
            cerr << v[iv][jv] << " ";               \
        }                                           \
        cerr << endl;                               \
    }
typedef long long ll;
// #define int ll

#define vi vector<int>
#define vl vector<ll>
#define vii vector<vector<int>>
#define vll vector<vector<ll>>
#define vs vector<string>
#define pii pair<int, int>
#define pis pair<int, string>
#define psi pair<string, int>
#define pll pair<ll, ll>
template <class S, class T>
pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) {
    return pair<S, T>(s.first + t.first, s.second + t.second);
}
template <class S, class T>
pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template <class S, class T>
ostream &operator<<(ostream &os, pair<S, T> p) {
    os << "(" << p.first << ", " << p.second << ")";
    return os;
}
#define X first
#define Y second
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define rrep(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define rrep1(i, n) for (int i = (int)(n); i > 0; i--)
#define REP(i, a, b) for (int i = a; i < b; i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(), c.end()
void YES(bool t = true) {
    cout << (t ? "YES" : "NO") << endl;
}
void Yes(bool t = true) { cout << (t ? "Yes" : "No") << endl; }
void yes(bool t = true) { cout << (t ? "yes" : "no") << endl; }
void NO(bool t = true) { cout << (t ? "NO" : "YES") << endl; }
void No(bool t = true) { cout << (t ? "No" : "Yes") << endl; }
void no(bool t = true) { cout << (t ? "no" : "yes") << endl; }
template <class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
    if (a > b) {
        a = b;
        return 1;
    }
    return 0;
}
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
int popcount(ll t) { return __builtin_popcountll(t); }
// int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
// int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
vi dx = {0, 1, 0, -1}, dy = {-1, 0, 1, 0};
// vi dx2 = { 1,1,0,-1,-1,-1,0,1 }, dy2 = { 0,1,1,1,0,-1,-1,-1 };
struct Setup_io {
    Setup_io() {
        ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
        cout << fixed << setprecision(25);
    }
} setup_io;
// const ll MOD = 1000000007;
const ll MOD = 998244353;
// #define mp make_pair
//#define endl '\n'

const int N = 200011;
// const int N = 4;
vector<vector<pll>> G(N);

vl dist(N);
vl sub(N);

void pre_dfs(int now, int par, ll w) {
    dist[now] = w;
    sub[now]++;

    for (auto [ch, x] : G[now]) {
        if (ch == par) continue;
        pre_dfs(ch, now, w ^ x);
        sub[now] += sub[ch];
    }
}

vector<map<ll, pii>> mps(N);
ll ans = 0;
int n;
void dfs(int now, int par) {
    // DEBUG(now);
    priority_queue<pii, vector<pii>, greater<pii>> pq;
    for (auto [ch, x] : G[now]) {
        if (ch == par) continue;
        dfs(ch, now);
        pq.push(pii(mps[ch].size(), ch));
    }

    // 自分の色
    ll x = dist[now];
    for (auto [ch, w] : G[now]) {
        if (ch == par) continue;

        // for (auto itr = mps[ch].begin(); itr != mps[ch].end(); itr++) {
        //     DEBUG(itr->first);
        //     DEBUG(itr->second);
        // }

        if (mps[ch].count(x)) {
            ans += mps[ch][x].second;
            // DEBUG(ans);
            ans += (ll)mps[ch][x].first * (n - sub[ch]);
            // DEBUG(ans);
        }
    }
    // DEBUG(ans);
    // 他の色
    while (pq.size() >= 2) {
        int u = pq.top().second;
        pq.pop();
        int v = pq.top().second;
        pq.pop();

        for (auto itr = mps[u].begin(); itr != mps[u].end(); itr++) {
            ll w = itr->first;
            if (w == x) continue;
            auto [n1, s1] = itr->second;
            if (mps[v].count(w)) {
                auto [n2, s2] = mps[v][w];

                ans += (ll)n1 * s2;
                ans += (ll)n2 * s1;
            }
            mps[v][w].first += n1;
            mps[v][w].second += s1;
        }

        pq.push(pii(mps[v].size(), v));
    }
    if (pq.size() == 1) {
        int u = pq.top().second;
        pq.pop();
        swap(mps[now], mps[u]);
    }
    // DEBUG(ans);

    mps[now][x].first = 1;
    mps[now][x].second = sub[now];
}

signed main() {
    cin >> n;

    rep(i, n - 1) {
        int u, v, c;
        cin >> u >> v >> c;
        u--;
        v--;
        G[u].emplace_back(v, c);
        G[v].emplace_back(u, c);
    }

    pre_dfs(0, -1, 0);
    // DEBUG_VEC(sub);
    dfs(0, -1);

    cout << (ll)n * (n - 1) - ans << endl;
}