#include <bits/stdc++.h>
template<class T> inline bool chmin(T&a, T b){if(a > b){a = b; return true;}else{return false;}}
template<class T> inline bool chmax(T&a, T b){if(a < b){a = b; return true;}else{return false;}}
#define ll long long
#define double long double
#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,n) for(int i=1;i<=(n);i++)
#define mod (ll)(1e9+7)
#define inf (ll)(3e18+7)
#define eps (double)(1e-9)
#define pi (double) acos(-1)
#define P pair<int,int>
#define PiP pair<int,pair<int,int>>
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
using namespace std;

struct edge{
    ll to, cost;
};

vector<int> cnt(110);
vector<P> vec;

void dfs(const vector<vector<edge>> &G, int v, int p){
    int ans = 0;
    for(auto nv : G[v]){
        if(nv.to == p)continue;
        dfs(G, nv.to, v);
        ans += cnt[nv.to];
        vec.push_back({nv.cost * cnt[nv.to], nv.cost});
    }
    cnt[v] = ans;
    if(ans == 0)cnt[v]++;
}

int main() {
    int n, k;
    cin >> n >> k;
    vector<vector<edge>> G(n);
    rep(i, n-1){
        ll a, b, c;
        cin >> a >> b >> c;
        a--; b--;
        G[a].push_back({b, c});
        G[b].push_back({a, c});
    }
    dfs(G, 0, -1);
    vector<P> s;
    rep(i, n-1){
        s.push_back({vec[i].first/vec[i].second, vec[i].second});
    }
    sort(rall(s));
    int ans = 0, sum = 0;
    rep(i, n-1){
        if(sum + s[i].second <= k){
            ans += s[i].first * s[i].second;
            sum += s[i].second;
        }
        ans += s[i].first * s[i].second;
    }
    cout << ans << endl;
}