using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var p = NList;
        var (n, k) = (p[0], p[1]);
        var map = NArr(n - 1);
        var tree = new List<(int id, int to)>[n];
        for (var i = 0; i < tree.Length; ++i) tree[i] = new List<(int id, int to)>();
        for (var i = 0; i < map.Length; ++i)
        {
            tree[map[i][0] - 1].Add((i, map[i][1] - 1));
            tree[map[i][1] - 1].Add((i, map[i][0] - 1));
        }
        var mul = new int[n - 1];
        DFS(0, -1, tree, mul);
        var dp = new long[k + 1];
        var ans = 0L;
        for (var i = 0; i < map.Length; ++i)
        {
            ans += map[i][2] * mul[i];
            var ndp = (long[]) dp.Clone();
            for (var j = 0; j < dp.Length && j + map[i][2] <= k; ++j)
            {
                ndp[j + map[i][2]] = Math.Max(ndp[j + map[i][2]], dp[j] + map[i][2] * mul[i]);
            }
            dp = ndp;
        }
        WriteLine(ans + dp.Max());
    }
    static int DFS(int cur, int prev, List<(int id, int to)>[] tree, int[] mul)
    {
        var count = 0;
        foreach (var next in tree[cur])
        {
            if (next.to == prev) continue;
            var sub = DFS(next.to, cur, tree, mul);
            mul[next.id] = sub;
            count += sub;
        }
        if (count == 0) ++count;
        return count;
    }
}