#include <bits/stdc++.h>
using namespace std;
int n, q;
int dp[105][105]; // dp[i][j] 子树i保留j条边最多多少苹果
struct Edge
{
    int v, w;
};
vector<Edge> e[105];
void dfs(int u, int fa)
{
    dp[u][0] = 0;
    for (int i = 0; i < e[u].size(); i++)
    {
        int v = e[u][i].v;
        int w = e[u][i].w;
        if (v == fa)
            continue;
        dfs(v, u);
        for (int j = q; j >= 0; j--) // u之前保留j条边
        {
            for (int k = 0; k + j + 1 <= q; k++) // v提供多少条边
            {
                //隐含条件：选择v下面的边时，u-v 之间的这条边包括进来了
                dp[u][j + k + 1] = max(dp[u][j + k + 1],
                                       dp[u][j] + dp[v][k] + w);
            }
        }
    }
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> q;
    for (int i = 1; i <= n - 1; i++)
    {
        int u, v, w;
        cin >> u >> v >> w;
        e[u].push_back((Edge){v, w});
        e[v].push_back((Edge){u, w});
    }
    dfs(1, 0);
    /*
    for (int i = 1; i <= n; i++)
    {
        for (int j = 0; j <= q; j++)
            cout << dp[i][j] << " ";
        cout << "\n";
    }
    */
    cout << dp[1][q] << "\n";
    return 0;
}