#include <bits/stdc++.h>
using namespace std;
template <class T, class T2>
inline void chkmax(T &x, const T2 &y) {
  if (x < y) x = y;
}
template <class T, class T2>
inline void chkmin(T &x, const T2 &y) {
  if (x > y) x = y;
}
const int MAXN = (1 << 10);
int n, k;
pair<int, int> ed[MAXN];
vector<pair<int, int> > adj[MAXN];
void read() {
  cin >> n >> k;
  for (int i = 0; i < n - 1; i++) {
    cin >> ed[i].first >> ed[i].second;
    adj[ed[i].first].push_back({ed[i].second, i});
    adj[ed[i].second].push_back({ed[i].first, i});
  }
}
vector<int> dp[MAXN];
vector<int> merge(vector<int> &x, vector<int> &y) {
  vector<int> ret;
  ret.assign(1 + min((int)x.size() + (int)y.size(), k), (int)1e9);
  for (int i = 1; i < (int)x.size(); i++)
    for (int j = 0; j < (int)y.size(); j++)
      if (i + j < (int)ret.size()) chkmin(ret[i + j], x[i] + y[j]);
  return ret;
}
void dfs(int u, int pr = -1) {
  dp[u].assign(2, 0);
  for (auto it : adj[u]) {
    int v = it.first;
    if (v == pr) continue;
    dfs(v, u);
    dp[u] = merge(dp[u], dp[v]);
  }
  dp[u][0] = 1;
}
vector<int> recreate(int u, int p, int pr = -1) {
  vector<int> ret;
  vector<int> nw_dp;
  nw_dp.assign(2, 0);
  vector<vector<int> > li;
  li.push_back(nw_dp);
  for (auto it : adj[u]) {
    int v = it.first;
    if (v == pr) continue;
    nw_dp = merge(li.back(), dp[v]);
    li.push_back(nw_dp);
  }
  for (int i = (int)adj[u].size() - 1; i >= 0; i--) {
    int v = adj[u][i].first;
    if (v == pr) continue;
    vector<int> curr = li.back();
    li.pop_back();
    ret.push_back(adj[u][i].second + 1);
    for (int q = 1; q < min(p, (int)dp[v].size()); q++)
      if (p - q < (int)li.back().size() &&
          dp[v][q] + li.back()[p - q] == curr[p]) {
        ret.pop_back();
        vector<int> tmp = recreate(v, q, u);
        for (int pppp : tmp) ret.push_back(pppp);
        p -= q;
        break;
      }
  }
  return ret;
}
vector<int> solve(int root) {
  vector<int> ret;
  for (int i = 1; i <= n; i++) dp[i].clear();
  dfs(root);
  ret = recreate(root, k);
  return ret;
}
void solve() {
  vector<int> answer = solve(1);
  for (int root = 2; root <= n; root++) {
    vector<int> tmp = solve(root);
    if (tmp.size() < answer.size()) answer = tmp;
  }
  if (answer.empty()) {
    cout << 0 << '\n';
    return;
  }
  sort(answer.begin(), answer.end());
  cout << answer.size() << '\n';
  for (int x : answer) cout << x << " ";
  cout << '\n';
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  read();
  solve();
  return 0;
}
