#include <bits/stdc++.h>
using namespace std;
#define int long long
const int MAX = 4e5, LOG = 18;
vector<int> dist(MAX);
vector<bool> vis(MAX);
vector<vector<pair<int, int>>> adjList(MAX);
vector<vector<pair<int, int>>> pa(MAX, vector<pair<int, int>>(LOG, make_pair(-1, -1)));
pair<int, int> kpa(int n, int k) {
int maxw = 0;
for (int i = 0; i < LOG; i++) {
if ((1 << i) & k) {
maxw = max(maxw, pa[n][i].second);
n = pa[n][i].first;
}
}
return make_pair(n, maxw);
}
int ans(int a, int b) {
int maxw, S = 0;
if (dist[a] < dist[b]) swap(a, b);
pair<int, int> res = kpa(a, S = dist[a] - dist[b]);
a = res.first;
maxw = res.second;
if (a == b) return maxw - S;
for (int i = LOG - 1; i >= 0; i--) {
if (pa[a][i].first != pa[b][i].first && pa[a][i].first != -1 && pa[b][i].first != -1) {
maxw = max(maxw, max(pa[a][i].second, pa[b][i].second));
a = pa[a][i].first;
b = pa[b][i].first;
S += (1 << (i + 1));
}
}
return max(maxw, max(pa[a][0].second, pa[b][0].second)) - S - 2;
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int N, K, Q, A, B, W, T = 0;
pair<pair<int, int>, int> curr;
vector<pair<pair<int, int>, int>> edges;
cin >> N >> K;
for (int i = 0; i < N - 1; i++) {
cin >> A >> B >> W;
edges.emplace_back(make_pair(--A, --B), W);
adjList[A].push_back(make_pair(W, B));
adjList[B].push_back(make_pair(W, A));
}
vis[0] = 1;
priority_queue<pair<pair<int, int>, int>, vector<pair<pair<int, int>, int>>, greater<pair<pair<int, int>, int>>> pq;
for (pair<int, int> adj: adjList[0]) pq.push(make_pair(adj, 0));
while (!pq.empty()) {
curr = pq.top();
pq.pop();
if (vis[curr.first.second]) continue;
vis[curr.first.second] = 1;
pa[curr.first.second][0] = make_pair(curr.second, curr.first.first);
dist[curr.first.second] = dist[curr.second] + 1;
T += curr.first.first;
for (pair<int, int> adj: adjList[curr.first.second]) {
if (!vis[adj.second]) {
pq.push(make_pair(adj, curr.first.second));
}
}
}
for (int j = 1; j < LOG; j++) {
for (int i = 1; i < N; i++) {
if (pa[i][j - 1].first == -1) continue;
pa[i][j].first = pa[pa[i][j - 1].first][j - 1].first;
pa[i][j].second = max(pa[i][j - 1].second, pa[pa[i][j - 1].first][j - 1].second);
}
}
A = 0;
for (int i = 0; i < N; i++) {
for (int j = 0; j < i; j++) {
// cout << i << "-" << j << "-" << ans(i, j) << endl;
if (ans(i, j) >= K) A++;
}
}
cout << (A << 1);
}
