#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<numeric>
#include<cmath>
#include<utility>
#include<tuple>
#include<cstdint>
#include<cstdio>
#include<iomanip>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<deque>
#include<unordered_map>
#include<unordered_set>
#include<bitset>
#include<cctype>
#include<chrono>
#include<random>
#include<cassert>
#include<cstddef>
#include<iterator>
#include<string_view>
#include<type_traits>

#ifdef LOCAL
#  include "debug_print.hpp"
#  define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define debug(...) (static_cast<void>(0))
#endif

using namespace std;
#define rep(i,n) for(int i=0; i<(n); i++)
#define rrep(i,n) for(int i=(n)-1; i>=0; i--)
#define FOR(i,a,b) for(int i=(a); i<(b); i++)
#define RFOR(i,a,b) for(int i=(b-1); i>=(a); i--)
#define ALL(v) v.begin(), v.end()
#define RALL(v) v.rbegin(), v.rend()
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );
#define pb push_back
using ll = long long;
using D = double;
using LD = long double;
using P = pair<int, int>;
template<typename T> using PQ = priority_queue<T,vector<T>>;
template<typename T> using minPQ = priority_queue<T, vector<T>, greater<T>>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
void yesno(bool flag) {cout << (flag?"Yes":"No") << "\n";}

template<typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
    os << p.first << " " << p.second;
    return os;
}
template<typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
    is >> p.first >> p.second;
    return is;
}

template<typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
    int s = (int)v.size();
    for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
    return os;
}
template<typename T>
istream &operator>>(istream &is, vector<T> &v) {
    for (auto &x : v) is >> x;
    return is;
}
void in() {}
template<typename T, class... U>
void in(T &t, U &...u) {
    cin >> t;
    in(u...);
}
void out() { cout << "\n"; }
template<typename T, class... U, char sep = ' '>
void out(const T &t, const U &...u) {
    cout << t;
    if (sizeof...(u)) cout << sep;
    out(u...);
}
void outr() {}
template<typename T, class... U, char sep = ' '>
void outr(const T &t, const U &...u) {
    cout << t;
    outr(u...);
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n,k; in(n,k);
    vector<vector<P>> g(n);
    rep(i,n-1){
        int a,b,c; in(a,b,c); a--; b--;
        g[a].pb({b,c});
        g[b].pb({a,c});
    }
    ll score = 0;
    vector<int> cnt_leaf(n);
    vector<int> weight(n);
    weight[0] = -1;
    vector<ll> delta(n);
    auto dfs = [&] (auto dfs, int u, int p) -> void{
        int ret = 0;
        for(auto [v,w] : g[u]){
            if(v == p) continue;
            dfs(dfs, v,u);
            ret += cnt_leaf[v];
            weight[v] = w;
        }
        if(ret == 0) ret = 1;
        cnt_leaf[u] = ret;
    };

    dfs(dfs,0,-1);
    FOR(i,1,n) delta[i] = (ll)cnt_leaf[i] * weight[i];
    score = accumulate(ALL(delta),0LL);

    ll dp[n][k+1];
    rep(i,n)rep(j,k+1) dp[i][j] = -1;
    dp[0][0] = 0;
    FOR(i,1,n)rep(j,k+1){
        if(dp[i-1][j] == -1) continue;
        chmax(dp[i][j], dp[i-1][j]);
        if(j + weight[i] <= k) chmax(dp[i][j+weight[i]], dp[i-1][j] + delta[i]);
    }
    ll maxd = 0;
    rep(i,k+1) chmax(maxd, dp[n-1][i]);
    out(score + maxd);
}