#include <bits/stdc++.h>
using namespace std;
#define int long long
#define INF (int)1e18
mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());
const int maxn = 3e5 + 69;
vector<pair<int, int>> adj[maxn];
bool type[maxn];
vector<int> ans;
int n, k;
int dfs(int c, int p, int len)
{
int ma = 0, mi = INF;
for(auto n2 : adj[c]) {
int n = n2.first;
int d = n2.second;
if(n==p) continue;
int l = dfs(n, c, d);
if(type[n]) mi = min(mi, l);
else ma = max(ma, l);
}
if(mi + ma > k) {
if(len == -1 || ma + len > k) {
type[c] = true;
ans.push_back(c);
return len;
}
type[c] = false;
return len + ma;
}
if(mi+len > k) {
type[c] = false;
return 0;
}
type[c] = true;
return len + mi;
}
void Solve()
{
cin>>n>>k;
for (int i=1; i<n; i++){
int a, b, c;
cin>>a>>b>>c;
adj[a-1].push_back({b-1, c});
adj[b-1].push_back({a-1, c});
}
dfs(0, -1, -1);
cout<<ans.size()<<"\n";
for (auto x: ans)cout<<x +1 <<" ";
}
int32_t main()
{
auto begin = std::chrono::high_resolution_clock::now();
ios_base::sync_with_stdio(0);
cin.tie(0);
int t = 1;
//cin >> t;
for(int i = 1; i <= t; i++)
{
//cout << "Case #" << i << ": ";
Solve();
}
auto end = std::chrono::high_resolution_clock::now();
auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n";
return 0;
}
