#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define TranLeThanhTam "TranLeThanhTam"
#define all(v) v.begin(),v.end()
#define reset(a,i) memset(a,i,sizeof(a))
#define FOR(i,a,b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i,a,b) for (int i = (a), _b = (b); i >= _b; --i)
#define compact(v) sort(all(v)), v.erase(unique(all(v)), end(v))
#define sz(v) (int) v.size()
#define MASK(i) (1 << (i))
typedef long long ll;
typedef long double lb;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
const int Thanh_Tam = 1e5 + 17;
const int inf = 1e9 + 17;
const long long infll = 1e18 + 17;
const int MOD = 1e9 + 7;
const int Log = 18;
const int dx[4] = {-1, 0, 0, 1};
const int dy[4] = {0, -1, 1, 0};
const int max_block_size = 270;
const ll P = 311;
const int maxA = 1e2 + 17;
const int addi = 1e9;
const char dir[4] = {'W', 'S', 'N', 'E'};
const int Mod[3] = {998244353, MOD, 759186269};
ll mul(ll a, ll b, ll mod);
ll binpow(ll a, ll b, ll mod)
{
ll res = 1;
while (b > 0)
{
if (b & 1) res = mul(res,a,mod);
b >>= 1;
a = mul(a,a,mod);
}
return res;
}
ll add(ll a, ll b, ll mod) { return (a + b) % mod; }
ll sub(ll a, ll b, ll mod) { return (a - b + mod) % mod; }
ll mul(ll a, ll b, ll mod) { return ((a % mod) * (b % mod)) % mod; }
ll div(ll a, ll b, ll mod) { return mul(a, binpow(b, mod - 2, mod), mod); }
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand_range(ll l, ll r) { return uniform_int_distribution<ll>(l,r)(rng); }
int n, ans_min = 0, ans_max = 0;
vector<int> adj[Thanh_Tam];
int used_min[Thanh_Tam], sz[Thanh_Tam], used_max[Thanh_Tam];
void dp_min(int u, int par)
{
vector<int> connect_child;
for (int v : adj[u])
{
if (v == par) continue;
dp_min(v, u);
if (used_min[v] == 0) connect_child.pb(v);
}
if (sz(connect_child))
{
ans_min += (sz(connect_child) << 1);
connect_child.pb(u);
connect_child.pb(connect_child[0]);
FOR(i,0,sz(connect_child) - 2)
{
used_min[connect_child[i]] = connect_child[i + 1];
sz[connect_child[i]] = sz(connect_child) - 1;
}
}
else if (par == 0)
{
int mx = 0;
for (int v : adj[u])
if (sz[v] < sz[mx]) mx = v;
ans_min += 2;
used_min[u] = used_min[mx];
used_min[mx] = u;
}
return;
}
pii find_node(int u, int par)
{
pii node = {0, u};
for (int v : adj[u])
{
if (v == par) continue;
pii tmp = find_node(v, u);
if (tmp > node) node = tmp;
}
++node.fi;
return node;
}
void prepare_dp_max()
{
int first_node = find_node(1, 0).se, second_node = find_node(first_node, 0).se;
cout << first_node << ' ' << second_node << '\n';
return;
}
void ThanhTam()
{
cin >> n;
FOR(i,2,n)
{
int u,v;
cin >> u >> v;
adj[u].pb(v);
adj[v].pb(u);
used_min[i] = used_max[i] = 0;
}
used_min[1] = used_max[1] = 0;
sz[0] = 1e9;
dp_min(1, 0);
cout << ans_min << '\n';
FOR(i,1,n) cout << used_min[i] << ' ';
cout << '\n';
//FOR(i,1,n) cout << used_max[i] << ' ';
return;
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
if (fopen(TranLeThanhTam".inp","r"))
{
freopen(TranLeThanhTam".inp","r",stdin);
freopen(TranLeThanhTam".out","w",stdout);
}
int t = 1;
//cin >> t;
while (t--)
ThanhTam();
return 0;
}
