/**
* author: wxhtzdy
* created: 02.07.2022 11:01:49
**/
#include <bits/stdc++.h>
using namespace std;
template <typename T>
class fenwick {
public:
vector<T> fenw;
int n;
fenwick(int _n) : n(_n) {
fenw.resize(n);
}
void modify(int x, T v) {
while (x < n) {
fenw[x] += v;
x |= (x + 1);
}
}
T get(int x) {
T v{};
while (x >= 0) {
v += fenw[x];
x = (x & (x + 1)) - 1;
}
return v;
}
};
long long Calc(vector<pair<int, int>> v, int k) {
int n = (int) v.size();
sort(v.begin(), v.end());
fenwick<int> fenw(n);
long long ans = 0;
for (int i = 0; i < n; i++) {
int d = min(v[i].first - v[i].second - k, n - 1);
ans += fenw.get(d);
fenw.modify(v[i].second, +1);
}
return ans;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, k;
cin >> n >> k;
vector<vector<pair<int, int>>> g(n);
for (int i = 0; i < n - 1; i++) {
int u, v, w;
cin >> u >> v >> w;
--u; --v;
g[u].emplace_back(v, w);
g[v].emplace_back(u, w);
}
long long ans = 0;
vector<int> sz(n);
vector<bool> was(n);
function<void(int, int)> Dfs = [&](int v, int pr) {
sz[v] = 1;
for (auto& e : g[v]) {
int u = e.first;
if (was[u] || u == pr) {
continue;
}
Dfs(u, v);
sz[v] += sz[u];
}
};
function<int(int, int, int)> Find = [&](int v, int pr, int n) {
for (auto& e : g[v]) {
int u = e.first;
if (was[u] || u == pr || sz[u] * 2 < n) {
continue;
}
return Find(u, v, n);
}
return v;
};
vector<pair<int, int>> vec;
function<void(int, int, int, int)> Go = [&](int v, int pr, int mx, int len) {
vec.emplace_back(mx, len);
for (auto& e : g[v]) {
int u = e.first;
int w = e.second;
if (!was[u] && u != pr) {
Go(u, v, max(mx, w), len + 1);
}
}
};
function<void(int)> Solve = [&](int v) {
Dfs(v, v);
v = Find(v, v, sz[v]);
was[v] = true;
vector<pair<int, int>> f;
f.emplace_back(0, 0);
for (auto& e : g[v]) {
int u = e.first;
int w = e.second;
if (!was[u]) {
Go(u, v, w, 1);
for (auto& p : vec) {
f.push_back(p);
}
ans -= Calc(vec, k);
vec.clear();
}
}
ans += Calc(f, k);
for (auto& e : g[v]) {
int u = e.first;
if (!was[u]) {
Solve(u);
}
}
};
Solve(0);
cout << ans * 2 << '\n';
return 0;
}
