#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 10;
const int mod = 1e9 + 7;
int read() {
  int x = 0, f = 1;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == '-') f = -1;
    c = getchar();
  }
  while (c >= '0' && c <= '9') x = (x << 1) + (x << 3) + c - '0', c = getchar();
  return x * f;
}
vector<int> g[N];
long long res = 0;
int ans[N], siz[N];
int n, rt;
void dfs1(int x, int fa) {
  siz[x] = 1;
  int mx = 0;
  for (int to : g[x]) {
    if (to == fa) continue;
    dfs1(to, x);
    mx = max(mx, siz[to]);
    siz[x] += siz[to];
  }
  if (n - siz[x] <= n / 2 && mx <= n / 2) rt = x;
}
int a[N], cnt, tot = 0;
void dfs2(int x, int fa, int de) {
  a[++tot] = x;
  for (int to : g[x]) {
    if (to == fa) continue;
    dfs2(to, x, de + 1);
  }
}
int main() {
  n = read();
  for (int i = 1; i <= n; i++) ans[i] = i;
  for (int i = 1; i < n; i++) {
    int u = read(), v = read();
    g[u].push_back(v);
    g[v].push_back(u);
  }
  dfs1(1, 0);
  dfs2(rt, 0, 0);
  for (int i = 1; i <= n; i++) res += 2ll * min(n - siz[i], siz[i]);
  for (int i = 1; i <= (tot) / 2; i++) swap(ans[a[i]], ans[a[(i + (tot) / 2)]]);
  ;
  if (tot & 1) {
    swap(ans[rt], ans[a[tot]]);
  }
  cout << res << endl;
  for (int i = 1; i <= n; i++) cout << ans[i] << " ";
  cout << endl;
}
