#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template<class T> using oset =
tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define int long long
#define ld long double
#define ar array
#define vi vector<int>
#define vii vector<vector<int>>
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define f first
#define s second
#define endl "\n"
const int MOD = 1e9+7;
const int inf = 1e9;
const int linf = 1e18;
const int d4i[4]={-1, 0, 1, 0}, d4j[4]={0, 1, 0, -1};
const int d8i[8]={-1, -1, 0, 1, 1, 1, 0, -1}, d8j[8]={0, 1, 1, 1, 0, -1, -1, -1};
// -------------------------------------------------- Main Code --------------------------------------------------
const int N = 3e5+5;
int n, k, isUsed[N];
vi ans;
vector<pii> g[N];
int dfs(int src, int par, int lastWt) {
int req = 0, ext = linf;
for (auto child : g[src]) {
int ch = child.f, wt = child.s;
if (ch == par) continue;
int x = dfs(ch, src, wt);
if (!isUsed[ch]) req = max(req, x);
else ext = min(ext, x);
}
if (ext+req <= k) {
isUsed[src] = true;
return lastWt+ext;
}
if (lastWt+req <= k) {
return lastWt+req;
}
ans.pb(src);
isUsed[src] = true;
return lastWt;
// have to add fire station on this node
}
void sol() {
cin >> n >> k;
for (int i = 0; i < n-1; i++) {
int a, b, c; cin >> a >> b >> c;
--a; --b;
g[a].pb({b, c});
g[b].pb({a, c});
}
dfs(0, -1, linf);
cout << ans.size() << endl;
reverse(all(ans));
for (auto i : ans) cout << i+1 << " "; cout << endl;
}
signed main () {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int t = 1;
// cin >> t;
while (t--) {
sol();
}
return 0;
}
