#include <bits/stdc++.h>
#include <atcoder/all>
typedef long long int ll;
typedef long long int ull;
#define MP make_pair
using namespace std;
using namespace atcoder;
typedef pair<ll, ll> P;
const ll MOD = 998244353;
// const ll MOD = 1000000007;
using mint = modint998244353;
// using mint = modint1000000007;
const double pi = 3.1415926536;
const int MAX = 2000003;
long long fac[MAX], finv[MAX], inv[MAX];
void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < MAX; i++){
        fac[i] = fac[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
        finv[i] = finv[i - 1] * inv[i] % MOD;
    }
}
// 二項係数計算
long long COM(int n, int k){
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
ll gcd(ll x, ll y) {
   if (y == 0) return x;
   else if (y > x) {
       return gcd (y, x); 
   }
   else return gcd(x % y, y);
}
ll lcm (ll x, ll y) {
   return x / gcd(x, y) * y;
}
ll my_sqrt(ll x) {
    ll m = 0;
    ll M = 3000000001;
    while (M - m > 1) {
        ll now = (M + m) / 2;
        if (now * now <= x) {
            m = now;
        }
        else {
            M = now;
        }
    }
    return m;
}
ll keta(ll n) {
    ll ret = 0;
    while (n) {
        n /= 10;
        ret++;
    }
    return ret;
}
ll ceil(ll n, ll m) {
    // n > 0, m > 0
    ll ret = n / m;
    if (n % m) ret++;
    return ret;
}
ll pow_ll(ll x, ll n) {
    if (n == 0) return 1;
    if (n % 2) {
        return pow_ll(x, n - 1) * x;
    }
    else {
        ll tmp = pow_ll(x, n / 2);
        return tmp * tmp;
    }
}

typedef struct {
    int to;
    int id;
} edge;

vector<edge> v[101];
int des[101]; // 辺iの子孫の数
int cst[101]; // 辺iのコスト

void dfs(int par, int cur, int now_id) {
    int d = 0;
    for (auto e : v[cur]) {
        if (e.to == par) continue;
        dfs(cur, e.to, e.id);
        d += des[e.id];
    }
    if ((v[cur].size() == 0) ||  ((v[cur].size() == 1) && (v[cur][0].to == par))) d++;
    des[now_id] = d;
}

int main() {
    int n, k;
    cin >> n >> k;
    
    for (int i = 1; i <= n - 1; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        edge e1, e2;
        e1.to = b;
        e1.id = i;
        cst[i] = c;
        v[a].push_back(e1);
        e2.to = a;
        e2.id = i;
        v[b].push_back(e2);
    }

    dfs(0, 1, 0);

    // for (int i = 1; i <= n - 1; i++) {
    //     cout << des[i] << ' ' << cst[i] << endl;
    // }

    int dp[n + 1][k + 1]; // i番目まででj長さ時の最大追加料
    for (int i = 0; i <= n; i++) {
        for (int j = 0; j <= k; j++) {
            dp[i][j] = 0;
        }
    }

    int first_ans = 0;
    for (int i = 1; i <= n - 1; i++) {
        first_ans += cst[i] * des[i];
    }
    // cout << first_ans << endl;

    for (int i = 0; i < n; i++) {
        for (int j = 0; j <= k; j++) {
            dp[i + 1][j] = max(dp[i][j], dp[i + 1][j]); // 追加しない
            if (j + cst[i + 1] <= k) {
                dp[i + 1][j + cst[i + 1]] = max(dp[i + 1][j + cst[i + 1]], dp[i][j] + des[i + 1] * cst[i + 1]);
            }
        }
    }
    int add = 0;
    for (int i = 0; i <= k; i++) {
        add = max(add, dp[n][i]);
    }
    cout << first_ans + add << endl;
    return 0;
}