#include <bits/stdc++.h>
template <class c>
int popc(c a) {
  if (sizeof(c) == 8)
    return __builtin_popcountll(a);
  else
    return __builtin_popcount(a);
}
template <class c>
int ctz(c a) {
  if (sizeof(c) == 8)
    return __builtin_ctzll(a);
  else
    return __builtin_ctz(a);
}
template <class c>
int clz(c a) {
  if (sizeof(c) == 8)
    return __builtin_clzll(a);
  else
    return __builtin_clz(a);
}
inline int min(const int &first, const int &second) {
  return (((second - first) >> (32 - 1)) & (first ^ second)) ^ first;
}
inline int max(const int &first, const int &second) {
  return (((second - first) >> (32 - 1)) & (first ^ second)) ^ second;
}
inline long long min(const long long &first, const long long &second) {
  return (((second - first) >> (64 - 1)) & (first ^ second)) ^ first;
}
inline long long max(const long long &first, const long long &second) {
  return (((second - first) >> (64 - 1)) & (first ^ second)) ^ second;
}
using namespace std;
char string_in_buffer[(int)260];
void fast_scan(int &first) { scanf("%d", &first); }
void fast_scan(long long &first) { scanf("%lld", &first); }
void fast_scan(unsigned long long &first) { scanf("%llu", &first); }
void fast_scan(double &first) { scanf("%lf", &first); }
void fast_scan(long double &first) { scanf("%Lf", &first); }
void fast_scan(char &first) {
  scanf("%c", &first);
  if (first == '\n') {
    fast_scan(first);
  }
}
void fast_scan(string &first) {
  scanf("%s", string_in_buffer);
  first = string(string_in_buffer);
}
template <class TFirst, class TSecond>
void fast_scan(pair<TFirst, TSecond> &p) {
  fast_scan(p.first);
  fast_scan(p.second);
}
template <class T>
void fast_scan(vector<T> &v) {
  for (auto &first : v) fast_scan(first);
}
void fast_print(const int &first) { printf("%d", first); }
void fast_print(const unsigned int &first) { printf("%u", first); }
void fast_print(const long long &first) { printf("%lld", first); }
void fast_print(const unsigned long long &first) { printf("%llu", first); }
void fast_print(const char &first) { printf("%c", first); };
void fast_print(const double &first) { printf("%.15lf", first); }
void fast_print(const long double &first) { printf("%.15Lf", first); }
void fast_print(const string &first) { printf("%s", first.c_str()); }
void fast_print(const char v[]) { fast_print((string)v); }
template <class TFirst, class TSecond>
void fast_print(const pair<TFirst, TSecond> &p) {
  fast_print(p.first);
  fast_print(' ');
  fast_print(p.second);
}
template <class T>
void fast_print(const vector<T> &v) {
  if (v.empty()) return;
  fast_print(v[0]);
  for (int i = 1; i < v.size(); i++) {
    fast_print(' ');
    fast_print(v[i]);
  }
}
template <class T>
void fast_print(const vector<vector<T>> &v) {
  if (v.empty()) return;
  fast_print(v[0]);
  for (int i = 1; i < v.size(); i++) {
    fast_print('\n');
    fast_print(v[i]);
  }
}
template <class T>
void fast_print(const T &v) {
  for (const auto &first : v) {
    fast_print(first);
    fast_print(' ');
  }
}
using namespace std;
namespace smart_io {
string print_start = "";
string sep = " ";
bool first_print = false;
void precall_print() {
  fast_print(print_start);
  print_start = "\n";
  first_print = true;
}
void _print(deque<string>) {}
template <class T, class... Args>
void _print(deque<string> names, T elem, Args... args) {
  if (!first_print) {
    fast_print("\n");
  } else {
    first_print = false;
  }
  fast_print(names.front());
  fast_print(" = ");
  fast_print(elem);
  names.pop_front();
  _print(names, args...);
}
}  // namespace smart_io
template <class T>
ostream &operator,(ostream &os, const T &object) {
  if (!smart_io::first_print) {
    fast_print(smart_io::sep);
  } else {
    smart_io::first_print = false;
  }
  fast_print(object);
  return os;
}
template <class T>
istream &operator,(istream &is, T &object) {
  fast_scan(object);
  return is;
}
namespace escape__from__random__aetuhoetnuhshe {
using namespace std::chrono;
mt19937 rng(duration_cast<milliseconds>(system_clock::now().time_since_epoch())
                .count());
uniform_real_distribution<> prob_dist(0.0, 1.0);
};  // namespace escape__from__random__aetuhoetnuhshe
namespace typedefs {}
namespace numbers_operation {
template <class T>
inline T floor_mod(T a, const T &b) {
  a %= b;
  if (a < 0) a += b;
  return a;
}
}  // namespace numbers_operation
using namespace numbers_operation;
using namespace typedefs;
using namespace escape__from__random__aetuhoetnuhshe;
int n;
vector<vector<int>> g;
vector<int> tsize;
void dfs0(int v, int _p) {
  tsize[v] = 1;
  for (int sub : g[v]) {
    if (sub == _p) continue;
    dfs0(sub, v);
    tsize[v] += tsize[sub];
  }
}
long long S = 0;
void dfs1(int v, int _p, int up) {
  for (int sub : g[v]) {
    if (sub == _p) continue;
    S += 2 * min(tsize[sub], tsize[v] + up - tsize[sub]);
    dfs1(sub, v, tsize[v] + up - tsize[sub]);
  }
}
struct Tree {
  int n;
  vector<int> _lca;
  vector<vector<int>> g, h;
  vector<int> tin, tout, tsize, pref, depth, head, tour;
  void dfs0(int v, int _p) {
    tsize[v] = 1;
    pref[v] = _p;
    for (int sub : g[v]) {
      if (sub == _p) continue;
      h[v].push_back(sub);
      depth[sub] = depth[v] + 1;
      dfs0(sub, v);
      tsize[v] += tsize[sub];
    }
    for (int j = 0; j < ((int)h[v].size()); j++)
      if (tsize[h[v][j]] > tsize[h[v][0]]) swap(h[v][j], h[v][0]);
  }
  void dfs1(int v, int &timer, int d) {
    tin[v] = timer++, head[v] = d;
    tour.push_back(v);
    if (!h[v].empty()) dfs1(h[v][0], timer, d);
    for (int j = 1; j < ((int)h[v].size()); j++) {
      int sub = h[v][j];
      dfs1(sub, timer, sub);
    }
    tout[v] = timer;
  }
  void init(vector<vector<int>> _g) {
    g = _g;
    n = ((int)g.size());
    tin.clear(), tout.clear(), tsize.clear(), h.clear(), pref.clear(),
        depth.clear(), _lca.clear(), head.clear(), tour.clear();
    tin.resize(n), tout.resize(n), tsize.resize(n), h.resize(n), pref.resize(n),
        depth.resize(n), head.resize(n);
    dfs0(0, -1);
    int timer = 0;
    dfs1(0, timer, 0);
    int t = 31 - __builtin_clz(n) + 1;
    _lca.resize(t * n);
    for (int i = 0; i < n; i++) _lca[tin[i]] = i;
    for (int i = 1; i < t; i++) {
      for (int j = 0; j < n; j++) {
        _lca[i * n + j] = _lca[(i - 1) * n + j];
        int k = j + (1 << (i - 1));
        if (k < n && depth[_lca[(i - 1) * n + k]] <= depth[_lca[i * n + j]])
          _lca[i * n + j] = _lca[(i - 1) * n + k];
      }
    }
  }
  bool anc(int v, int u) { return tin[v] <= tin[u] && tout[u] <= tout[v]; }
  int get_subtree_size(int v, int root) {
    if (anc(v, root)) {
      return n - tsize[next(v, root)];
    } else
      return tsize[v];
  }
  pair<int, int> get_range(int v) { return make_pair(tin[v], tout[v]); }
  int lca(int a, int b) {
    if (anc(a, b)) return a;
    if (anc(b, a)) return b;
    a = tin[a], b = tin[b];
    if (a > b) swap(a, b);
    int p = 31 - __builtin_clz(b - a + 1);
    a = _lca[p * n + a];
    b = _lca[p * n + b - (1 << p) + 1];
    return pref[(depth[a] < depth[b]) ? a : b];
  }
  int jump(int v, int k) {
    while (v != -1) {
      int u = head[v];
      if (k <= depth[v] - depth[u]) {
        return tour[tin[v] - k];
      } else {
        k -= depth[v] - depth[u] + 1;
        v = pref[u];
      }
    }
    assert(false);
  }
  int next(int a, int b) {
    if (a == b) return a;
    if (anc(a, b)) {
      a = tin[a] + 1, b = tin[b];
      int p = 31 - __builtin_clz(b - a + 1);
      a = _lca[p * n + a];
      b = _lca[p * n + b - (1 << p) + 1];
      return depth[a] < depth[b] ? a : b;
    } else
      return pref[a];
  }
  int dist(int a, int b) { return depth[a] + depth[b] - 2 * depth[lca(a, b)]; }
  vector<pair<int, int>> decompose_up(int up, int down) {
    vector<pair<int, int>> ranges;
    while (head[down] != head[up]) {
      ranges.emplace_back(tin[down], tin[head[down]]);
      down = pref[head[down]];
    }
    if (up != down) ranges.emplace_back(tin[down], tin[up] + 1);
    return ranges;
  }
  vector<pair<int, int>> decompose(int a, int b, bool include_lca) {
    int c = lca(a, b);
    vector<pair<int, int>> path = decompose_up(c, a);
    if (include_lca) path.emplace_back(tin[c], tin[c]);
    vector<pair<int, int>> end = decompose_up(c, b);
    for (int i = ((int)end.size()) - 1; ~i; i--)
      path.emplace_back(end[i].second, end[i].first);
    return path;
  }
};
struct CentroidTree : public Tree {
  int estimate_size(int v, int _p, const vector<bool> &used) {
    int sz = 1;
    for (int sub : g[v]) {
      if (sub == _p) continue;
      if (used[sub]) continue;
      sz += estimate_size(sub, v, used);
    }
    return sz;
  }
  int collect_centroids(int v, int _p, const int &N, int &C1, int &C2,
                        const vector<bool> &used) {
    int sz = 1;
    bool centroid = true;
    for (int sub : g[v]) {
      if (sub == _p) continue;
      if (!used.empty() && used[sub]) continue;
      int t = collect_centroids(sub, v, N, C1, C2, used);
      if (2 * t > N) centroid = false;
      sz += t;
    }
    if (centroid && sz * 2 >= N) {
      if (C1 == -1)
        C1 = v;
      else
        C2 = v;
    }
    return sz;
  }
  vector<int> find_centroids(int traverse, const vector<bool> &used) {
    int a = -1, b = -1;
    collect_centroids(traverse, -1,
                      used.empty() ? n : estimate_size(traverse, -1, used), a,
                      b, used);
    vector<int> rez;
    if (a != -1) rez.push_back(a);
    if (b != -1) rez.push_back(b);
    return rez;
  }
  vector<int> find_centroids() { return find_centroids(0, {}); }
};
void collect(int v, int _p, vector<int> &nodes) {
  nodes.push_back(v);
  for (int sub : g[v]) {
    if (sub == _p) continue;
    collect(sub, v, nodes);
  }
}
signed main(signed argc, char *argv[]) {
  cin, n;
  g.resize(n);
  for (int i = 0; i < (n - 1); i++) {
    int a, b;
    cin, a, b;
    a--;
    b--;
    g[a].push_back(b);
    g[b].push_back(a);
  }
  tsize.resize(n);
  dfs0(0, -1);
  dfs1(0, -1, 0);
  smart_io::precall_print();
  cout, S;
  CentroidTree tree;
  tree.init(g);
  vector<int> c = tree.find_centroids();
  if (((int)c.size()) == 2) {
    vector<int> parts[2];
    collect(c[0], c[1], parts[0]);
    collect(c[1], c[0], parts[1]);
    assert(((int)parts[0].size()) == ((int)parts[1].size()));
    vector<int> next(n);
    for (int i = 0; i < ((int)parts[0].size()); i++) {
      next[parts[0][i]] = parts[1][i];
      next[parts[1][i]] = parts[0][i];
    }
    for (auto &first : next) {
      first++;
    }
    smart_io::precall_print();
    cout, next;
  } else {
    vector<int> all;
    collect(c[0], -1, all);
    vector<int> next(n);
    for (int i = 0; i < ((int)all.size()); i++) {
      next[all[i]] = all[(i + ((int)all.size()) / 2) % ((int)all.size())];
    }
    for (auto &first : next) {
      first++;
    }
    smart_io::precall_print();
    cout, next;
  }
}
