#include <bits/stdc++.h>
using namespace std;
#define kien long long
#define int long long
#define pb push_back
#define FOR(i, a, b) for (int i = a;i <= b; i++)
#define FORD(i, a, b) for (int i = a;i >= b; i--)
#define pii pair<int, int>
#define dembit(a) __builtin_popcountll(a)
#define task "kien"
#define fin(x) freopen(x".inp","r",stdin)
#define fou(x) freopen(x".out","w",stdout)
#define debug(x) cout << x << " ";
#define down cout << "\n"
const kien MOD = 1e9 + 7;
const int NTEST = 100;
const int Million = 1e6 + 5;
const int MXN = 1e5 + 5;
mt19937 rd(chrono::high_resolution_clock::now().time_since_epoch().count());
kien rand(kien l, kien r) {
assert(l <= r);
return uniform_int_distribution<kien>(l, r)(rd);
}
kien n, k, m, dem, sz[MXN + 5], u, v, a[1000000];
kien maxx, minn, vtr, l, r, ans;
bool vis[MXN];
vector <pii> dp[MXN];
vector <pii> vec;
struct FenwickTree {
int N;
kien bit[MXN];
void init(int n) {
N = n;
for (int i = 1; i <= N; i++) bit[i] = 0;
}
void update(int pos, int val) {
for (; pos <= N; pos += pos & -pos) bit[pos] += val;
}
kien get(int pos) {
kien s = 0;
for (; pos > 0; pos -= pos & -pos) s += bit[pos];
return s;
}
} BIT;
void calcsz (int u, int pa) {
sz[u] = 1;
for (auto v : dp[u]) {
if (v.first != pa and !vis[v.first]) {
calcsz(v.first, u);
sz[u] += sz[v.first];
}
}
}
int centroid (int u, int pa, int N) {
for (auto v : dp[u]) {
if (v.first != pa and !vis[v.first] and sz[v.first] > N / 2) {
return centroid(v.first , u, N);
}
}
return u;
}
void dfs (int u, int len ,int maxx, int pa) {
vec.pb({maxx, len});
for (auto v : dp[u]) {
if (v.first == pa or vis[v.first]) continue;
dfs(v.first, len + 1, max(maxx, v.second), u);
}
}
void build (int u) {
calcsz(u, 0);
int cen = centroid(u, 0, sz[u]);
vis[cen] = 1;
vector<pii>().swap(vec); /// giải phóng bộ nhớ
for (auto v : dp[cen]) {
if (!vis[v.first]) dfs (v.first, 1, v.second, cen);
}
sort (vec.begin(), vec.end());
for (auto v : vec) {
if (v.first - v.second - k >= 0) {
ans += BIT.get(v.first - v.second - k);
ans++;
}
BIT.update(v.second, 1);
}
for (auto v : vec) {
BIT.update(v.second, -1);
}
for (auto u : dp[cen]) {
if (!vis[u.first]) {
vector<pii>().swap(vec);
dfs (u.first, 1, u.second, cen);
sort (vec.begin(), vec.end());
for (auto v : vec) {
if (v.first - v.second - k >= 0) ans -= BIT.get(v.first - v.second - k);
BIT.update(v.second, 1);
}
for (auto v : vec) {
BIT.update(v.second, -1);
}
}
}
for (auto v : dp[cen]) {
if (!vis[v.first]) build(v.first);
}
}
void solve() {
cin >> n >> k;
kien w;
FOR (i, 1, n - 1) {
cin >> u >> v >> w;
dp[u].pb({v, w}); dp[v].pb({u, w});
}
BIT.init(100000);
build (1);
cout << ans * 2;
}
main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
if (fopen(task".inp", "r")) {
fin(task); fou(task);
}
int t = 1; //cin >> t;
while(t--) solve();
cerr << "\n" << 1.0 * clock() / CLOCKS_PER_SEC << "s ";
}
