/**
* @file main.cpp
* @author tnknguyen_ (
[email protected])
* @date 08-05-2024
*
* @copyright Copyright (c) 2024
* https://oj.vnoi.info/problem/coci2021_r4_janjetina
*/
#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define ll long long
#define len(s) (int)s.size()
#define pii pair<int, int>
//#define int long long
struct BIT{
int n;
vector<ll> f;
BIT(int N = 1e5): n(N+5), f(N+5, 0) {};
void update(int i, int val){
++i;
while(i < n){
f[i] += val;
i += (i & -i);
}
}
ll get(int i){
ll ans = 0;
++i;
while(i > 0){
ans += f[i];
i -= (i & -i);
}
return ans;
}
ll get(int l, int r){
return get(r) - get(l-1);
}
};
const int MX = 1e5 + 5;
vector<pii> gr[MX];
int del[MX], sz[MX];
int n, k;
BIT bit;
ll ans = 0;
int dfs(int u, int p){
sz[u] = 1;
for(pii e : gr[u]){
int v = e.first;
if(v != p && !del[v]){
sz[u] += dfs(v, u);
}
}
return sz[u];
}
int centroid(int u, int p, const int &n){
for(pii e : gr[u]){
int v = e.first;
if(v != p && !del[v] && sz[v]*2 > n){
return centroid(v, u, n);
}
}
return u;
}
vector<pii> vals;
void calc(int u, int p, int len, int _max){ // Calculates vals[].
vals.push_back({_max, len});
for(pii e : gr[u]){
int v, c;
tie(v, c) = e;
if(v != p && !del[v]){
calc(v, u, len + 1, max(_max, c));
}
}
}
void solve(const int &op){ //update answer
sort(vals.begin(), vals.end());
for(pii p : vals){
int w, l;
tie(w, l) = p;
int need = w - l - k;
ans += (bit.get(need) * op);
bit.update(l, 1);
}
for(pii p : vals){
bit.update(p.second, -1);
}
}
void decompose(int u){ // Centroid Decomposition
dfs(u, 0);
u = centroid(u, 0, sz[u]);
del[u] = 1;
vals.clear();
calc(u, 0, 0, 0);
solve(1);
for(pii e : gr[u]){
int v, c;
tie(v, c) = e;
if(!del[v]){
vals.clear();
calc(v, 0, 1, c);
solve(-1);
}
}
for(pii e : gr[u]){
int v = e.first;
if(!del[v]){
decompose(v);
}
}
}
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
// freopen("main.inp","r",stdin);
// freopen("main.out","w",stdout);
cin>>n>>k;
for(int i=1; i<n; ++i){
int u, v, w;
cin>>u>>v>>w;
gr[u].push_back({v, w});
gr[v].push_back({u, w});
}
decompose(1);
cout<<ans*2;
return 0;
}
