#include <bits/stdc++.h>
#define pb push_back
#define f first
#define s second
using namespace std;
typedef long long ll;
typedef long double ld;
const ll oo = 1e18 + 10;
const ll N = 1e6 + 10;
const ll M1 = 1e6;
ll n, k;
ll a1[N];
vector <pair<ll, ll> > a[N];
ll mn[N];
bool Check(ll mx)
{
mx++;
ll k1 = 1, ls = 1;
ll i = 1;
while (i < n)
{
if (ls > 0)
{
ls += a1[i];
if (ls > mx)
{
ls = -1;
continue;
}
}
else
{
ls -= a1[i];
if (ls < -mx)
{
ls = 1;
k1++;
}
}
i++;
}
return k1 <= k;
}
void Rec(ll x, ll y, ll ds)
{
mn[x] = min(mn[x], ds);
for (auto i : a[x])
if (i.f != y)
{
Rec(i.f, x, ds + i.s);
}
}
int main()
{
ios_base::sync_with_stdio(0);
iostream::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> k;
if (n <= 20)
{
for (ll i = 0; i < n - 1; i++)
{
ll x, y, z;
cin >> x >> y >> z;
a[--x].pb({--y, z});
a[y].pb({x, z});
}
ll ans = oo, nom = 0;
for (ll msk = (1 << n) - 1; msk >= 0; msk--)
{
ll k1 = 0;
for (ll j = 0; j < n; j++)
if ((msk >> j) & 1) k1++;
if (k1 != k) continue;
for (ll j = 0; j < n; j++) mn[j] = oo;
for (ll j = 0; j < n; j++)
if ((msk >> j) & 1) Rec(j, j, 0);
ll mx = 0;
for (ll j = 0; j < n; j++) mx = max(mx, mn[j]);
if (mx < ans) ans = mx, nom = msk;
}
cout << ans << endl;
for (int i = 0; i < n; i++)
if ((nom >> i) & 1) cout << i + 1 << " ";
cout << endl;
return 0;
}
for (ll i = 1; i < n; i++)
{
cin >> a1[i] >> a1[i] >> a1[i];
}
ll l = 0, r = oo;
while (l < r)
{
ll mdl = (l + r) >> 1;
if (Check(mdl)) r = mdl;
else l = mdl + 1;
}
cout << l << endl;
}
/*
5 1
1 2 3
2 3 4
3 4 5
4 5 6
*/
