#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cmath>
#include <map>
#include <queue>
#include <iomanip>
#include <set>
#include <tuple>
#define mkp make_pair
#define mkt make_tuple
#define rep(i,n) for(int i = 0; i < (n); ++i)
using namespace std;
typedef long long ll;
const ll MOD=1e9+7;
template<class T> void chmin(T &a,const T &b){if(a>b) a=b;}
template<class T> void chmax(T &a,const T &b){if(a<b) a=b;}

struct Centroid{
    vector<vector<int>> g;
    vector<int> sz,dead;

    Centroid(){}
    Centroid(int V):sz(V,1),dead(V,0),g(V){}

    void initialize(int V){
      sz.resize(V,1);
      dead.resize(V,0);
      g.resize(V);
    }

    void add_edge(int u,int v){
        g[u].push_back(v);
        g[v].push_back(u);
    }

    int szdfs(int now,int par){
        sz[now]=1;
        for(auto nex:g[now]){
            if(nex==par||dead[nex]) continue;
            sz[now]+=szdfs(nex,now);
        }
        return sz[now];
    }

    void findCentroid(int now,int par,int V,vector<int> &cens){
        bool ok=true;
        for(auto nex:g[now]){
            if(nex==par||dead[nex]) continue;
            findCentroid(nex,now,V,cens);
            if(sz[nex]>V/2) ok=false;
        }
        if(V-sz[now]>V/2) ok=false;
        if(ok) cens.push_back(now);
    }

    vector<int> build(int root){
        vector<int> cens;
        szdfs(root,-1);
        findCentroid(root,-1,sz[root],cens);
        return cens;
    }

    void kill(int now){
        dead[now]=1;
    }

    bool alive(int now){
        return dead[now]==0;
    }
};

struct Edge{
  int to,col;
  Edge(int to,int col):to(to),col(col){}
};

Centroid cent;
int N,K;
vector<vector<Edge>> g;

map<pair<int,int>,int> twoCol;
map<int,int> two,one;
int oneCol;

map<pair<int,int>,int> tcol;
map<int,int> tmp,omp;
int ocol;

ll calc(int now,int par,int fir,int sec){
  ll res=0;
  if(sec==-1){
    res+=two[fir]-tmp[fir];
    res+=(oneCol-ocol)-(one[fir]-omp[fir]);

    one[fir]++;omp[fir]++;
    oneCol++;ocol++;
  }else{
    res+=twoCol[minmax(fir,sec)]-tcol[minmax(fir,sec)]+1;
    res+=one[fir]-omp[fir];
    res+=one[sec]-omp[sec];

    twoCol[minmax(fir,sec)]++;tcol[minmax(fir,sec)]++;
    two[fir]++;two[sec]++;
    tmp[fir]++;tmp[sec]++;
  }

  for(auto e:g[now]){
    if(cent.alive(e.to)==false) continue;
    if(e.to==par) continue;
    
    if(sec==-1){
      if(fir==e.col) res+=calc(e.to,now,fir,sec);
      else res+=calc(e.to,now,fir,e.col);
    }else{
      if(fir==e.col||sec==e.col) res+=calc(e.to,now,fir,sec);
    }
  }
  return res;
}

ll solve(int now){
  vector<int> cs=cent.build(now);
  int C=cs[0];
  cent.kill(C);
  twoCol.clear();two.clear();one.clear();
  oneCol=0;

  ll res=0;
  for(auto e:g[C]){
    if(cent.alive(e.to)==false) continue;

    tcol.clear();tmp.clear();omp.clear();
    ocol=0;

    res+=calc(e.to,C,e.col,-1);
  }
  
  for(auto e:g[C]){
    if(cent.alive(e.to)==false) continue;

    res+=solve(e.to);
  }
  return res;
}

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  cin>>N>>K;
  cent.initialize(N);
  g.resize(N);
  rep(i,N-1){
    int a,b,c;
    cin>>a>>b>>c;
    a--;b--;
    g[a].push_back({b,c});
    g[b].push_back({a,c});
    cent.add_edge(a,b);
  }

  cout<<solve(0)<<endl;

  return 0;
}