#include <bits/stdc++.h>

using namespace std;
using ll = long long;

ll N, K;
vector<vector<pair<ll, ll>>> E;
vector<ll> subtree;
vector<vector<ll>> dp;
vector<pair<ll, ll>> D;

ll subtree_size(ll from, ll p){
    ll cnt = 0;
    for (auto [to, C] : E[from]){
        if (to == p) continue;
        cnt += subtree_size(to, from);
        D.push_back({C, C*subtree[to]});
    }

    if (cnt == 0) cnt = 1;

    return subtree[from] = cnt;
}

int main(){

    ll A, B, C, x, y, ans=0;
    cin >> N >> K;
    
    E.resize(N);
    subtree.resize(N);
    
    for (int i=0; i < N-1; i++){
        cin >> A >> B >> C;
        A--; B--;
        E[A].push_back({B, C});
        E[B].push_back({A, C});
    }

    subtree_size(0, -1); 

    vector<vector<ll>> dp(N, vector<ll>(K+1));
    
    for (int i=1; i<=N-1; i++){
        tie(x, y) = D[i-1];
        ans += y;
        for (int j=0; j<=K; j++){
            if (j-x>=0) dp[i][j] = max(dp[i][j], dp[i-1][j-x]+y);
            dp[i][j] = max(dp[i][j], dp[i-1][j]);
        }
    }

    cout << ans + dp[N-1][K] << endl;

    return 0;
}