#include <bits/stdc++.h>
#define gibon ios::sync_with_stdio(false); cin.tie(0);
#define fir first
#define sec second
#define pdd pair<double, double>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pmax pair<__int128, __int128>
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
typedef long long ll;
using namespace std;
int dx[4]={0, 1, 0, -1}, dy[4]={1, 0, -1 , 0};
const int mxN=300005;
const int mxM=1010;
const int mxK=105;
const int MOD=1000000007;
const ll INF=1e18;
const ll P1=1000000009;
const ll P2=1000000009;
int N;
ll K;
ll station[mxN];
ll town[mxN];
bool Chk[mxN];
vector <pll> v[mxN];
int ans;
void dfs(int now, int pre, ll dis)
{
station[now]=INF;
town[now]=0;
for(pll nxt : v[now]) if(nxt.fir!=pre)
{
dfs(nxt.fir, now, nxt.sec);
station[now]=min(station[now], station[nxt.fir]+nxt.sec);
town[now]=max(town[now], town[nxt.fir]+nxt.sec);
}
if(now==1)
{
if(town[now]>K-station[now])
{
Chk[now]=true;
ans++;
}
return;
}
if(town[now]<=K-station[now]) town[now]=-INF;
if(town[now]+dis>K)
{
Chk[now]=true;
ans++;
station[now]=0;
town[now]=-INF;
}
}
int main()
{
gibon
cin >> N >> K;
for(int i=1;i<N;i++)
{
ll a, b, c;
cin >> a >> b >> c;
v[a].emplace_back(b, c);
v[b].emplace_back(a, c);
}
dfs(1, -1, 0);
cout << ans << '\n';
for(int i=1;i<=N;i++)
{
if(Chk[i]) cout << i << " ";
}
}
