#include <bits/stdc++.h>
using namespace std;
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii ;
typedef pair<ll, ll> pll ;
typedef vector<pii> vii ;
typedef vector<int> veci ;
typedef vector<pll> vll ;
typedef vector<ll> vecll;
// find_by_order order_of_key
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define F first
#define S second
#define pb push_back
#define endl '\n'
#define Mp make_pair
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " = " << x << endl
#define set_dec(x) cout << fixed << setprecision(x);
#define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io freopen("in.txt" , "r" , stdin) ; freopen("out.txt" , "w" , stdout);
#define lb lower_bound
#define ub upper_bound
#define for1(n) for(int i=1;i<=n;i++)
#define for0(n) for(int i=0;i<n;i++)
#define forn(n) for(int i=n;i>0;i--)
#define pq priority_queue <pii, vector<pii>, greater<pii>>
const ll mod = 1e9+7 ;// 998244353 ;// 1e9+9;
ll inf=1e18;
const int N=1e6+100,L=21,bs=701;
int A[N],B[N],C[N],D[N],E[N],n,m,k,q,dp[N],vis[N],sz[N],fen[N],nn;
vector<pii>g[N],vec;
ll ans;
void upd(int i,int x){
for(i++;i<N;i+=i&-i)fen[i]+=x;
}
int get(int i){
int ans=0;
for(i++;i>0;i-=i&-i)ans+=fen[i];
return ans;
}
void DFS(int v,int p=0){
sz[v]=1;
for(auto [u,w]:g[v])if(u!=p && vis[u]==0){
DFS(u,v);
sz[v]+=sz[u];
}
}
int cen(int v,int p=0){
for(auto[u,w]:g[v])if(vis[u]==0 && u!=p && sz[u]>nn/2)return u;
return v;
}
void dfs(int v,int p=0,int l=0,int w=0){
vec.pb({w,l});
for(auto [u,ww]:g[v])if(u!=p && vis[u]==0)dfs(u,v,l+1,max(w,ww));
}
void solve(int root){
DFS(root);nn=sz[root];
root=cen(root);
dfs(root);
sort(all(vec));
for(pii p:vec){
int w=p.F,l=p.S;
ans+=get(w-l-k);
upd(l,1);
}
for(pii p:vec)upd(p.S,-1);
vec.clear();vis[root]=2;
for(auto [u,w]:g[root])if(vis[u]==0)solve(u);
}
int main(){
fast_io
cin>>n>>k;
for1(n-1){
int u,v,w;cin>>u>>v>>w;
g[u].pb({v,w});
g[v].pb({u,w});
}
solve(1);
cout<<ans*2<<endl;
}
