// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>
using namespace std;
#define nl '\n'
#define pb push_back
#define mp make_pair
#define f first
#define s second
#define sz(x) int(x.size())
template<class T> using V = vector<T>;
using pi = pair<int, int>;
using vi = V<int>;
using vpi = V<pi>;
using ll = long long;
using pl = pair<ll, ll>;
using vpl = V<pl>;
using vl = V<ll>;
using db = long double;
const int MOD = 1e9 + 7;
const ll INFL = ll(1e16) + 10;
int main() {
cin.tie(0)->sync_with_stdio(0);
int N; ll K; cin >> N >> K;
V<vpi> adj(N); for(int i = 0; i < N-1; i++) {
int u, v, w; cin >> u >> v >> w; --u, --v;
adj[u].pb(mp(v, w));
adj[v].pb(mp(u, w));
}
vi ans;
function<pl(int, int, ll)> dfs = [&](int u, int p, ll d) {
ll close = -INFL, far = 0;
for(auto& e : adj[u]) {
auto [v, w] = e; if (v == p) continue;
pl R = dfs(v, u, w);
if (R.f) {
close = max(close, R.s);
} else {
far = max(far, R.s);
}
}
pl R;
if (close >= far) {
R = mp(1, close - d);
} else {
R = mp(0, far + d);
}
if (R.f && R.s < 0) R = mp(0, 0);
if (!R.f && R.s > K) {
ans.pb(u); R = mp(1, K - d);
}
return R;
};
dfs(0, -1, INFL);
cout << sz(ans) << nl;
for(auto& x : ans) cout << x + 1 << " ";
cout << nl;
return 0;
}
