#include <bits/stdc++.h>
#define REP(i, n) for (int i = 0; (i) < (int)(n); ++ (i))
using namespace std;

int64_t solve(int n, const vector<vector<pair<int, int> > > & g) {
    int64_t ans = 0;
    function<map<int, int> (int, int)> go = [&](int x, int parent) {
        int sum_one = 0;
        map<int, int> one;
        map<pair<int, int>, int> two;
        for (auto [y, c] : g[x]) if (y != parent) {
            auto sub = go(y, x);
            for (auto [d, k] : sub) if (d != c) {
                ans += (int64_t)k;
                ans += (int64_t)k * two[minmax({ c, d })];
                ans += (int64_t)k * (one.count(c) ? one[c] : 0);
                ans += (int64_t)k * (one.count(d) ? one[d] : 0);
                two[minmax({ c, d })] += k;
            }
            int k = 1 + (sub.count(c) ? sub[c] : 0);
            ans += (int64_t)k * (sum_one - (one.count(c) ? one[c] : 0));
            one[c] += k;
            sum_one += k;
        }
        return one;
    };
    go(0, -1);
    return ans;
}

int main() {
    int n, k; cin >> n >> k;
    vector<vector<pair<int, int> > > g(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);
    }
    cout << solve(n, g) << endl;
    return 0;
}