#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<int, int> pii;
typedef pair<ld, ld> pld;
int n, k;
int bit[100009];
void upd(int idx, int val){
for(++idx; idx <= 100000; idx += idx&(-idx))
bit[idx] += val;
}
int get(int idx){
int ret = 0;
for(++idx; idx > 0; idx -= idx&(-idx))
ret += bit[idx];
return ret;
}
vector<pii> g[100009];
int subsz[100009];
int block[100009];
void getsz(int v, int prt){
subsz[v] = 1;
for(auto u : g[v])
if(u.ff != prt && !block[u.ff]){
getsz(u.ff, v);
subsz[v] += subsz[u.ff];
}
}
int getcentroid(int v, int prt, int tot){
for(auto u : g[v])
if(u.ff != prt && !block[u.ff] && subsz[u.ff]*2 >= tot)
return getcentroid(u.ff, v, tot);
return v;
}
vector<pll> child[100009];
void dfs(int v, int prt,int d, int curmax, int top){
child[top].pb({curmax, d});
for(auto u : g[v])
if(u.ff != prt && !block[u.ff])
dfs(u.ff, v, d+1, max(curmax, u.ss), top);
}
vector<int> rel;
ll mx = 1e5;
ll ans;
void getans(int v){
getsz(v, 0);
v = getcentroid(v, 0, subsz[v]);
// cout << v << endl;
vector<pii> vec;
for(auto u : g[v]){
if(block[u.ff]) continue;
dfs(u.ff, v, 1, u.ss, u.ff);
sort(all(child[u.ff]));
for(auto u : child[u.ff]){
if(u.ff-u.ss-k >= 0){
ans += 1;
ans -= 1*get(u.ff-u.ss-k);
}
upd(u.ss, 1);
}
for(auto u : child[u.ff]){
upd(u.ss, -1);
vec.pb(u);
}
}
sort(all(vec));
for(auto u : vec){
if(u.ff-u.ss-k >= 0){
ans += 1*get(u.ff-u.ss-k);
}
upd(u.ss, 1);
}
for(auto u : vec){
upd(u.ss, -1);
}
for(auto u : g[v])
child[u.ff].clear();
block[v] = 1;
for(auto u : g[v])
if(!block[u.ff])
getans(u.ff);
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
//freopen("in.txt", "r", stdin);
//freopen("out.txt", "w", stdout);
cin >> n >> k;
for(int i = 0; i < n-1; ++i){
int x, y, z;
cin >> x >> y >> z;
g[x].pb({y, z});
g[y].pb({x, z});
}
getans(1);
cout << ans * 2 << '\n';
}
