#include <cassert>
#include <iostream>
#include <vector>
#include <map>
using namespace std;

long long ans = 0;

pair<long long,long long> dfs(const vector<vector<pair<long long,long long>>> &G, long long v, long long p, long long c){
  map<long long,long long> C;
  map<long long,long long> D;
  vector<pair<long long,long long>> Q;
  long long s = 1, d = 0, f = 0;
  for(auto e : G[v]){
    if(e.first == p){
      Q.emplace_back(-10,-10);
      continue;
    }
    auto q = dfs(G,e.first,v,e.second);
    Q.push_back(q);
    C[e.second] += q.first;
    D[e.second] += q.second;
    f += q.first;
    if(e.second == c) s += q.first, d += q.second;
    else d += q.first;
    ans += q.second;
    // diff += q.second;
  }
  long long diff = 0;
  for(size_t i = 0; i < G[v].size(); ++i){
    if(G[v][i].first == p) continue;
    // assert(Q[i] >= 0);
    // ans += Q[i].first*(f-C[G[v][i].second]);
    diff += Q[i].first*(f-C[G[v][i].second]);
    ans += Q[i].first*(D[G[v][i].second]-Q[i].second);
  }
  assert(diff%2 == 0);
  ans += diff/2;
  return {s,d};
}

int main(){
  long long N, K;
  cin >> N >> K;
  vector<vector<pair<long long,long long>>> G(N);
  for(int i = 1; i < N; ++i){
    long long u, v, c;
    cin >> u >> v >> c;
    --u,--v,--c;
    G[u].emplace_back(v,c);
    G[v].emplace_back(u,c);
  }
  dfs(G,0,-1,-100);
  cout << ans << endl;
}