#include<bits/stdc++.h>
using namespace std;
using i64 = long long;
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n,k;
cin >> n >> k;
vector<vector<pair<int,int>>> adj(n);
for(int i = 0;i < n - 1;i++){
int u,v,w;
cin >> u >> v >> w;
u --;
v --;
adj[u].push_back({v,w});
adj[v].push_back({u,w});
}
assert(n <= 17);
const i64 inf = 1e18;
vector<bool> is(n,false);
vector<i64> sub(n,inf);
function<void(int,int)> dfs1 = [&](int u,int p){
if(is[u]) sub[u] = 0LL;
for(auto pa : adj[u]){
int v = pa.first;
int w = pa.second;
if(v == p) continue;
dfs1(v,u);
sub[u] = min(sub[u],sub[v] + w);
}
};
vector<i64> dp(n,inf);
function<void(int,int,i64)> dfs2 = [&](int u,int p,i64 mini){
dp[u] = min(mini,sub[u]);
for(auto pa : adj[u]){
int v = pa.first;
int w = pa.second;
if(v == p) continue;
dfs2(v,u,min(mini,sub[u]) + w);
}
};
int best = (1 << n) - 1;
for(int i = 0;i < (1 << n);i++){
for(int j = 0;j < n;j++){
if(i & (1 << j)){
is[j] = true;
}else{
is[j] = false;
}
sub[j] = dp[j] = inf;
}
dfs1(0,0);
dfs2(0,0,inf);
bool ok = true;
for(int j = 0;j < n;j++){
if(dp[j] > (i64)k){
ok = false;
break;
}
}
if(ok && __builtin_popcount(i) < __builtin_popcount(best)){
best = i;
}
}
cout << __builtin_popcount(best) << '\n';
for(int i = 0;i < n;i++){
if((1 << i) & best){
cout << i + 1 << " ";
}
}
cout << '\n';
return 0;
}
