#include <bits/stdc++.h>
#define task "BriantheCrab"
#define int long long
#define pii pair <int, int>
#define fi first
#define se second
#define szf sizeof
#define sz(s) (int)((s).size())
#define all(v) (v).begin(), (v).end()
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using namespace std;
template <class T> void minimize (T &t, T f) {if (t > f) t = f;}
template <class T> void maximize (T &t, T f) {if (t < f) t = f;}
const int maxN = 2e5 + 5;
const int inf = 1e18 + 7;
const int mod = 1e9 + 7;
int n, k;
int sz[maxN];
bool del[maxN];
vector<pii> adj[maxN];
vector<pii> paths;
int res;
struct fenwick {
int bit[maxN * 2];
fenwick () {
memset (bit, 0, sizeof (bit));
}
void update (int x, int val) {
for (; x < maxN; x += x & -x) {
bit[x] += val;
}
}
int get (int x) {
int res = 0;
for (; x > 0; x -= x & -x) {
res += bit[x];
}
return res;
}
} T;
int dfsSz (int u, int p) {
sz[u] = 1;
for (auto [v, w] : adj[u]) {
if (v == p || del[v]) {
continue;
}
sz[u] += dfsSz (v, u);
}
return sz[u];
}
int findCen (int u, int p, int num) {
for (auto [v, w] : adj[u]) {
if (v == p || del[v]) {
continue;
}
if (sz[v] > num / 2) {
return findCen (v, u, num);
}
}
return u;
}
void dfs (int u, int p, int dep, int val) {
paths.push_back ({val, dep});
for (auto [v, w] : adj[u]) {
if (v == p || del[v]) {
continue;
}
dfs (v, u, dep + 1, max (val, w));
}
}
int cal (vector <pii> &Path) {
sort (all (Path));
int curAns = 0;
for (auto [w, len] : Path) {
if (w >= len) {
curAns += T.get (w - len);
}
T.update (k + len, 1);
}
for (auto [w, len] : Path) {
T.update (k + len, -1);
}
return curAns;
}
void demp (int u) {
u = findCen (u, 0, dfsSz (u, 0));
del[u] = true;
paths.clear ();
dfs (u, 0, 0, 0);
res += cal (paths);
for (auto [v, w] : adj[u]) {
if (!del[v]) {
paths.clear ();
dfs (v, u, 1, w);
res -= cal (paths);
}
}
for (auto [v, w] : adj[u]) {
if (!del[v]) {
demp (v);
}
}
}
void solve () {
cin >> n >> k;
for (int i = 0; i < n - 1; i ++) {
int u, v, w;
cin >> u >> v >> w;
adj[u].push_back ({v, w});
adj[v].push_back ({u, w});
}
demp (1);
cout << res * 2 << '\n';
return;
}
signed main () {
cin.tie (nullptr) -> sync_with_stdio (false);
if (fopen (task".inp", "r")) {
freopen (task".inp", "r", stdin);
freopen (task".out", "w", stdout);
}
int t = 1;
while (t --) {
solve ();
}
return 0;
}
// thfv
