#include<bits/stdc++.h>
using namespace std;
using Int = long long;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;
}

struct Centroid{
  vector<int> sz,dead;
  vector< vector<int> > G;
  Centroid(){}
  Centroid(int n):sz(n,1),dead(n,0),G(n){}

  void add_edge(int u,int v){
    G[u].emplace_back(v);
    G[v].emplace_back(u);
  }

  int dfs(int v,int p){
    sz[v]=1;
    for(int u:G[v])
      if(u!=p&&!dead[u]) sz[v]+=dfs(u,v);
    return sz[v];
  }

  void find(int v,int p,int tmp,vector<int> &cs) {
    int ok=1;
    for (int u:G[v]){
      if(u==p||dead[u]) continue;
      find(u,v,tmp,cs);
      ok&=(sz[u]<=tmp/2);
    }
    ok&=(tmp-sz[v]<=tmp/2);
    if(ok) cs.push_back(v);
  }

  vector<int> build(int r) {
    int tmp=dfs(r,-1);
    vector<int> cs;
    find(r,-1,tmp,cs);
    return cs;
  }

  void disable(int v){
    dead[v]=1;
  }

  void enable(int v){
    dead[v]=0;
  }

  int alive(int v){
    return !dead[v];
  }
};


template<typename F>
struct FixPoint : F{
  FixPoint(F&& f):F(forward<F>(f)){}
  template<typename... Args>
  decltype(auto) operator()(Args&&... args) const{
    return F::operator()(*this,forward<Args>(args)...);
  }
};
template<typename F>
inline decltype(auto) MFP(F&& f){
  return FixPoint<F>{forward<F>(f)};
}


template<typename V>
V compress(V v){
  sort(v.begin(),v.end());
  v.erase(unique(v.begin(),v.end()),v.end());
  return v;
}

template<typename T>
map<T, int> dict(const vector<T> &v){
  map<T, int> res;
  for(int i=0;i<(int)v.size();i++)
    res[v[i]]=i;
  return res;
}

map<char, int> dict(const string &v){
  return dict(vector<char>(v.begin(),v.end()));
}

struct FastIO{
  FastIO(){
    cin.tie(0);
    ios::sync_with_stdio(0);
  }
}fastio_beet;

//INSERT ABOVE HERE
signed main(){
  using ll = long long;

  int n,k;
  cin>>n>>k;

  using P = pair<int, int>;
  vector< map<int, int> > col(n);
  Centroid G(n);
  for(int i=1;i<n;i++){
    int x,y,z;
    cin>>x>>y>>z;
    x--;y--;z--;
    G.add_edge(x,y);
    col[x][y]=z;
    col[y][x]=z;
  }

  queue<int> que;
  que.emplace(G.build(0)[0]);

  ll ans=0;
  vector<int> cnt(k,0),uku(k,0);
  vector<P> ps(n);

  while(!que.empty()){
    int r=que.front();que.pop();
    auto calc=
      [&](P p,int q)->P{
        assert(~p.first);
        if(p.first==q||p.second==q) return p;
        if(p.second==-1) return minmax({p.first,q});
        return P(-1,-1);
      };

    vector<P> vp;
    for(int t:G.G[r]){
      if(!G.alive(t)) continue;

      MFP([&](auto dfs,int v,int p,P st)->void{
            if(st.first<0) return;
            for(int u:G.G[v]){
              if(u==p) continue;
              if(!G.alive(u)) continue;
              dfs(u,v,calc(st,col[u][v]));
            }
            if(st.second!=-1){
              vp.emplace_back(st);
            }
          })(t,r,P(col[r][t],-1));
    }
    vp=compress(vp);
    auto idx=[&](P p){return lower_bound(vp.begin(),vp.end(),p)-vp.begin();};

    vector<int> num(vp.size());
    int all=0;
    for(int t:G.G[r]){
      if(!G.alive(t)) continue;

      // count
      MFP([&](auto dfs,int v,int p,P st)->void{
            ps[v]=st;
            if(st.first<0) return;
            for(int u:G.G[v]){
              if(u==p) continue;
              if(!G.alive(u)) continue;
              dfs(u,v,calc(st,col[u][v]));
            }
            if(st.second==-1){
              ans+=all-cnt[st.first];
              ans+=uku[st.first];
            }else{
              ans+=1;
              ans+=cnt[st.first];
              ans+=cnt[st.second];
              ans+=num[idx(st)];
            }
          })(t,r,P(col[r][t],-1));

      // paint
      MFP([&](auto dfs,int v,int p)->void{
            P st=ps[v];
            if(st.first<0) return;
            for(int u:G.G[v]){
              if(u==p) continue;
              if(!G.alive(u)) continue;
              dfs(u,v);
            }
            if(st.second==-1){
              cnt[st.first]++;
              all++;
            }else{
              num[idx(st)]++;
              uku[st.first]++;
              uku[st.second]++;
            }
          })(t,r);
    }

    for(int t:G.G[r]){
      if(!G.alive(t)) continue;

      // clear
      MFP([&](auto dfs,int v,int p)->void{
            P st=ps[v];
            if(st.first<0) return;
            for(int u:G.G[v]){
              if(u==p) continue;
              if(!G.alive(u)) continue;
              dfs(u,v);
            }
            if(st.second==-1){
              cnt[st.first]--;
            }else{
              uku[st.first]--;
              uku[st.second]--;
            }
          })(t,r);
    }

    G.disable(r);
    for(int u:G.G[r])
      if(G.alive(u))
        que.emplace(G.build(u)[0]);
  }

  cout<<ans<<endl;
  return 0;
}