#include <bits/stdc++.h>
using namespace std;
const long long nax = 405;
vector<vector<long long>> kp[nax];
set<long long> g[nax];
long long n, k;
long long mn = (1LL << 62), mr = -1;
void dfs(long long u, long long p) {
  g[u].erase(p);
  for (auto &k : g[u]) dfs(k, u);
  kp[u].resize(((long long)g[u].size()) + 1,
               vector<long long>(nax, (1LL << 32)));
  kp[u][0][1] = 1;
  long long i = 0;
  for (auto &k : g[u]) {
    i++;
    for (long long j = 0; j < nax; j++)
      for (long long b = j; b < nax; b++)
        kp[u][i][b] = min(kp[u][i][b], kp[u][i - 1][b - j] +
                                           kp[k][((long long)g[k].size())][j]);
  }
  kp[u][((long long)g[u].size())][0] = 1;
  if (kp[u][((long long)g[u].size())][k] + (u != p) < mn) {
    mn = kp[u][((long long)g[u].size())][k] + (u != p);
    mr = u;
  }
}
set<long long> capital;
void dfs2(long long u, long long l) {
  if (l == 0) return;
  capital.insert(u);
  if (l == 1) return;
  long long i = ((long long)g[u].size());
  for (auto it = g[u].rbegin(); it != g[u].rend(); it++) {
    long long k = *it;
    for (long long j = 0; j < l; j++) {
      if (kp[u][i - 1][l - j] + kp[k][((long long)g[k].size())][j] ==
          kp[u][i][l]) {
        l -= j;
        dfs2(k, j);
        break;
      }
    }
    i--;
  }
}
vector<pair<long long, long long>> v;
int32_t main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> k;
  for (long long i = 0; i < n - 1; i++) {
    long long x, y;
    cin >> x >> y;
    v.push_back({x, y});
    g[x].insert(y);
    g[y].insert(x);
  }
  dfs(1, 1);
  dfs2(mr, k);
  vector<long long> ans;
  for (long long i = 0; i < n - 1; i++) {
    long long a = 0, b = 0;
    a = (capital.find(v[i].first) != capital.end());
    b = (capital.find(v[i].second) != capital.end());
    if (a != b) ans.push_back(i + 1);
  }
  cout << ((long long)ans.size()) << endl;
  for (auto &k : ans) cout << k << endl;
}
