#include <iostream>
#include <vector>
#include <fstream>
#include <cmath>
using namespace std;

struct node {
    int key;
    node *l, *r, *p;
    int h;
};
struct things {
    int key, l, r;
    node *q;
    int lh, rh, h;
    int flag;
};
int balf(vector < things > &arr, int i)
{
    if ( i < 0)
    {
        return -1;
    }
    arr[i].lh = 1 + balf(arr, arr[i].l);
    arr[i].rh = 1 + balf(arr, arr[i].r);
    arr[i].h = arr[i].rh - arr[i].lh;
    arr[i].q->h = max(arr[i].lh, arr[i].rh);

    return max(arr[i].lh, arr[i].rh);
}

int mheight(node *peak)
{
    if ( peak == NULL)
    {
        return -1;
    }
    return max(1 + mheight(peak->l), 1 + mheight(peak->r));
}

void bigleft(node *peak, node *&root)
{
    if (peak->p == NULL || peak == root)//root
    {
        root = peak->r->l;
        peak->r->l->p = NULL;
    } else if (peak->p->l == peak) //wl
    {
        peak->p->l = peak->r->l;
        peak->r->l->p = peak->p;
    } else if (peak->p->r == peak) //wr
    {
        peak->p->r = peak->r->l;
        peak->r->l->p = peak->p;
    }
    node *tmpl = peak->r->l->l;
    node *tmpr = peak->r->l->r;
    peak->r->l->l = peak;
    peak->r->l->r = peak->r;
    peak->p = peak->r->l;
    peak->r->p = peak->r->l;
    peak->p->r->l = tmpr;
    peak->p->l->r = tmpl;

}

void smallleft(node *peak, node *&root)
{
    if (peak->p == NULL || peak == root) //root
    {
        root = peak->r;
        peak->r->p = NULL;
    } else if (peak->p->l == peak) //wl
    {
        peak->p->l = peak->r;
        peak->r->p = peak->p;
    } else if (peak->p->r == peak) //wr
    {
        peak->p->r = peak->r;
        peak->r->p = peak->p;
    }
    node *tmpl = peak->r->l;
    peak->r->l = peak;
    peak->p = peak->r;
    peak->r = tmpl;

}

void setf(node *peak, vector < things > &res, int i)
{
    if (peak != NULL)
    {
        if (peak->l != NULL)
        {
            res[2*i + 1].key = peak->l->key;
            res[2*i + 1].flag = 0;
            if (peak->l->l == NULL)
            {
                res[2*i + 1].l = -1;
            } else {
                res[2*i + 1].l = 2*(2*i+1)+1;
            }
            if (peak->l->r == NULL)
            {
                res[2*i + 1].r = -1;
            } else {
                res[2*i + 1].r = 2*(2*i+1)+2;
            }

            setf(peak->l, res, i + 1);
        }
        if (peak->r != NULL)
        {
            res[2*i + 2].key = peak->r->key;
            res[2*i + 2].flag = 0;
            if (peak->r->l == NULL)
            {
                res[2*i + 2].l = -1;
            } else {
                res[2*i + 2].l = 2*(2*i+2)+1;
            }
            if (peak->r->r == NULL)
            {
                res[2*i + 2].r = -1;
            } else {
                res[2*i + 2].r = 2*(2*i+2)+2;
            }

            setf(peak->r, res, i + 2);
        }
    }
}
int arrsize(int loop)
{
    int c = 0;
    int remain = 1;
    if (loop == 0)
    {
        return remain;
    } else {
        while (c != loop)
        {
            c++;
            remain = remain + pow(2, c);
        }
        return remain;
    }
}

int main()
{
    ifstream fin("rotation.in");
    ofstream fout("rotation.out");

    vector < things > arr;

    int n;
    int m;
    fin >> n;
    m = n;
    if (n > 1)
    {
        arr.resize(n);
        int key, num1, num2;
        node *parent = NULL;
        for (int i = 0; i < n; i++)
        {
            fin >> key >> num1 >> num2;
            arr[i].key = key;
            arr[i].l = --num1;
            arr[i].r = --num2;

            node *q = NULL;
            q = new node();
            q->key = key;
            q->l = NULL;
            q->r = NULL;
            q->p = parent;
            arr[i].q = q;
            parent = q;
        }
        for (int i = 0; i < n; i++)
        {
            arr[i].q->l = arr[arr[i].l].q;
            arr[i].q->r = arr[arr[i].r].q;
        }
        node *root = arr[0].q;
        for (int i = 0; i < n; i++)
        {
        //  cout << arr[i].q->key<< " "<< arr[i].l<< " "<< arr[i].r<<endl;
        }
    //  cout << "array filled\n";
        balf(arr, 0);
        for (int i = 0; i < n; i++)
        {
            if (arr[i].h > 1)
            {
                if (arr[arr[i].r].h == -1)
                {
                    bigleft(root, root);
                } else {
                    smallleft(root, root);
                }
                i = n +1;
            }
        }
        int size = arrsize(mheight(root));

        things some;
        some.flag = 1;
        vector < things > res (size, some);
        setf(root, res, 0);

        fout << n << endl;

        res[0].key = root->key;
        res[0].flag = 0;
        if (root->l == NULL && root->l == NULL)
        {
            res[0].l = -1;
            res[0].l = -1;
        } else {
            res[0].l = 1;
            res[0].r = 2;
            if (root->l == NULL)
            {
                res[0].l  =  -1;
            }
            if (root->r == NULL)
            {
                res[0].r  =  -1;
            }
        }
        int j = 3;
        int c = 0;
        for (int i = 0; i < size; i++)
        {
            if (res[i].flag == 0)
            {
                c++;
                if (i > 0 && c <= (n/2))
                {
                    if (res[i].l != -1 && res[i].r != -1)
                    {
                        res[i].l = j;
                        res[i].r = j + 1;
                        j = j + 2;
                    } else if (res[i].l == -1 && res[i].r != -1)
                    {
                        res[i].r = j;
                        j = j + 1;
                    } else if (res[i].l != -1 && res[i].r == -1)
                    {
                        res[i].l = j;
                        j = j + 1;
                    }
                }
                fout << res[i].key<<" "<< ++res[i].l<<" " << ++res[i].r <<endl;
            }
        }
    } else {
        if (n == 0)
        {
            fout << 0<<endl;
        } else if (n == 1)
        {
            fout << n<<endl;
            int key;
            fin >> key;
            fout<< key<<" "<<0<<" "<<0<<endl;
        }
    }

}