#include <bits/stdc++.h>
#define maxN 5002
using namespace std;
int n, v[maxN], ans;
bool used[maxN];
struct piv
{
    int a, b, c;
} p[maxN];
int Min(int x, int y)
{
    if (x < y)
        return x;
    return y;
}

int Max(int x, int y)
{
    if (x > y)
        return x;
    return y;
}
void read()
{
    int i;
    freopen("sortare.in", "r", stdin);
    scanf("%d", &n);
    for (i = 2; i <= n; ++ i)
        scanf("%d %d %d", &p[i].a, &p[i].b, &p[i].c);
}
void sortp(int len, int left, int d)
{
    int i, x = left, y = left + len - 1, m, M;
    if (d > ans)
        ans = d;

    m = Min(Min(p[len].a, p[len].b), p[len].c);
    M = Max(Max(p[len].a, p[len].b), p[len].c);

    if (p[len].a != p[len].b && p[len].b != p[len].c && p[len].c != p[len].a)
        ++ x, -- y;
    if (len < 2)
        {
            m = M = 0;
            x = 1;
            y = n;
        }
    while (x <= y)
    {
        if (!used[x])
        {
            v[left + m] = x;
            used[x] = 1;
            if (len >= 2)
            {
                sortp(x - left, left, d + 1);
                sortp(len - x + left - 1, x + 1, d + 1);
            }
            break;
        }
        else
            if (!used[y])
        {
            v[left + M] = y;
            used[y] = 1;
            if (len >= 2)
            {
                sortp(y - left, left, d + 1);
                sortp(len - y + left - 1, y + 1, d + 1);
            }
            break;
        }
        ++ x;
        -- y;
    }
}
void solve()
{
    int i;
    sortp(n, 1, 1);
}
void write()
{
    int i;
    freopen("sortare.out", "w", stdout);
    printf("%d\n", ans);
    for (i = 1; i <= n; ++ i)
        printf("%d ", v[i]);
}
int main()
{
    read();
    solve();
    write();
    return 0;
}