#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/trie_policy.hpp>
#define ST first
#define ND second
#define PB push_back
using namespace std;
using namespace __gnu_pbds;
using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;
typedef tree<pi,null_type,less<pi>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
const int nax = 100 * 1000 + 10, INF = 1e9;
int n, k;
vector<pi>V[nax];
bool mark[nax];
int dp[nax];
vi all;
ll ans;
ordered_set S;
void dfs(int x, int p) {
dp[x] = 1;
all.PB(x);
for(auto nbh : V[x]) if(nbh.ST != p && !mark[nbh.ST]) {
dfs(nbh.ST, x);
dp[x] += dp[nbh.ST];
}
}
vector<pi>path;
void dfsC(int x, int p, int l, int mx) {
path.emplace_back(mx, l);
for(auto nbh : V[x]) if(nbh.ST != p && !mark[nbh.ST]) {
dfsC(nbh.ST, x, l + 1, max(mx, nbh.ND));
}
}
void centro(int x) {
all.clear();
path.clear();
dfs(x, 0);
int c = x;
for(int y : all) if(dp[y] < dp[c] && 2 * dp[y] >= dp[x]) c = y;
dfsC(c, 0, 0, 0);
sort(path.begin(), path.end());
int id = 1;
for(auto [w, l] : path) {
//cerr << c << ": " << w << " " << l << " " << S.order_of_key({w - l - k + 1, INF}) << "\n";
ans += S.order_of_key({w - l - k, INF});
S.insert({l, id++});
}
//cout << ans << "\n";
S.clear();
mark[c] = true;
for(auto nbh : V[c]) if(!mark[nbh.ST]) {
id = 1;
path.clear();
dfsC(nbh.ST, c, 1, nbh.ND);
sort(path.begin(), path.end());
for(auto [w, l] : path) {
ans -= S.order_of_key({w - l - k, INF});
S.insert({l,id++});
}
S.clear();
centro(nbh.ST);
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> k;
for(int a, b, c, i = 1; i < n; ++i) {
cin >> a >> b >> c;
V[a].emplace_back(b, c);
V[b].emplace_back(a, c);
}
centro(1);
cout << ans * 2;
}
