#include<fstream>
using namespace std;
int n, i, nr;
int v[5005];
struct str{
    int a, b, c;
};
str w[5005];
ifstream fin("sortare.in");
ofstream fout("sortare.out");
void modif(int st, int dr){
    for(int i = dr; i >= st; i--){
        v[i + 1] = v[i];
    }
}
void solve(int n){
    nr++;
    if(n == 1){
        v[1] = 1;
        return;
    }
    if(w[n].a != w[n].b && w[n].b != w[n].c && w[n].b != w[n].c){
        solve(n - 2);
        modif(w[n].a, n - 2);
        v[ w[n].a ] = n - 1;
        modif(w[n].b, n - 1);
        v[ w[n].b ] = n;
    }
    else{
        solve(n - 1);
        int x;
        if(w[n].a == w[n].b || w[n].a == w[n].c){
            x = w[n].a;
        }
        else{
            x = w[n].b;
        }
        modif(x, n - 1);
        v[x] = n;
    }
}
int main(){
    fin>> n;
    for(i = 2; i <= n; i++){
        fin>> w[i].a >> w[i].b >> w[i].c;
    }
    solve(n);
    fout<< nr <<"\n";
    for(i = 1; i <= n; i++){
        fout<< v[i] <<" ";
    }
    return 0;
}