#include <bits/stdc++.h>
using namespace std;
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define int long long
using ar = array<int, 2>;
const int64_t INF = 1ll << 60;
const int N = 1e5 + 5;
vector<bool> del(N);
int sub[N], ptr, M[N], h[N], k, n, bit[N], ans;
vector<ar> adj[N], VV, V[N];
void add(int r, int d) {
r++;
for (; r < N; r += r & -r) bit[r] += d;
}
int get(int r) {
r++;
int re = 0;
for (; r > 0; r &= (r - 1)) re += bit[r];
return re;
}
void find_sub(int v, int p) {
sub[v] = 1;
for (auto P: adj[v]) {
int u = P[0];
if (del[u] || u == p) continue;
find_sub(u, v);
sub[v] += sub[u];
}
}
int find_center(int v, int p, int kol) {
for (auto P: adj[v]) {
int u = P[0];
if (del[u] || u == p || sub[u] <= (kol / 2)) continue;
return find_center(u, v, kol);
}
return v;
}
void dfs(int v, int p) {
for (auto P: adj[v]) {
int u = P[0], w = P[1];
if (u == p || del[u]) continue;
M[u] = max(M[v], w);
h[u] = h[v] + 1;
dfs(u, v);
}
V[ptr].push_back({M[v], h[v]});
VV.push_back({M[v], h[v]});
}
int solve(vector<ar> &a) {
sort(a.begin(), a.end());
int ans = 0;
for (auto P: a) {
int m = P[0], h = P[1];
ans += get(m - h - k);
add(h, +1);
}
for (auto P: a)
add(P[1], -1);
return ans;
}
void rec(int x) {
find_sub(x, x);
int c = find_center(x, x, sub[x]);
del[c] = true;
for (auto P: adj[c]) {
int u = P[0], w = P[1];
if (del[u]) continue;
h[u] = 1, M[u] = w;
dfs(u, c);
ptr++;
}
FOR(i, 0, ptr) {
ans -= solve(V[i]);
V[i].clear();
}
VV.push_back({-INF, 0});
ans += solve(VV);
VV.clear();
ptr = 0;
for (auto P: adj[c]) {
int u = P[0], w = P[1];
if (del[u]) continue;
rec(u);
}
}
signed main() {
ios::sync_with_stdio(0), cin.tie(0);
cin >> n >> k;
FOR(i, 1, n) {
int u, v, w;
cin >> u >> v >> w;
u--, v--;
adj[v].push_back({u, w});
adj[u].push_back({v, w});
}
rec(0);
cout << 2ll * ans << '\n';
}
//20:55:05
