#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define F first
#define S second
#define coy cout<<"YES\n"
#define con cout<<"NO\n"
#define co1 cout<<"-1\n"
#define sc(x) scanf("%lld",&x)
#define all(x) x.begin(),x.end()
#define fast ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
using namespace std;
const int SI=2e5+7;
ll INF=8e18+7;
int MOD=1e9+7;
int dx[] = {1 , -1 , 0 , 0};
int dy[] = {0 , 0 , 1 , -1};
int T=1;
ll ss;
ll n,dp[SI],up[SI],ans[SI];
vector < ll> v[SI];
void bt( int x=1,int pa=0)
{
for (auto i:v[x])
{
if (i==pa)
continue;
bt(i,x);
if (up[i]==0)
{
swap(ans[x],ans[i]);
ss+=2;
up[x]=1;
}
}
}
void solver()
{
cin>>n;
ans[n]=n;
for (int i=1;i<n;i++)
{
ans[i]=i;
int a,b;
cin>>a>>b;
v[a].pb(b);
v[b].pb(a);
}
bt();
if(ans[1]==1)
ss+=2,swap(ans[1],ans[v[1].back()]);
cout <<ss<<" 0\n";
for (int i=1;i<=n;i++)
cout <<ans[i]<<" ";
for (int i=1;i<=n;i++)
cout <<ans[i]<<" ";
}
int main()
{
//fast
while (T--)
solver();
return 0;
}
