#include <bits/stdc++.h>
using namespace std;
ifstream fin ("ctc.in"); ofstream fout ("ctc.out");
#define MAXN 100005;

vector <int> adj[MAXN], con, idx, lowlink, in_stack;
vector<vector <int> > c;
stack <int> S;
int index;

void read_in (vector<int>* andj, int &n)
{
    int cnt_edges, x, y;
    fin >> n;
    for (fin >> cnt_edges; cnt_edges > 0; --cnt_edges)
        fin >> x >> y, adj[x - 1].push_back(y - 1);
    fin.close();
}

void print_out (const <vector < vector <int> >& G)
{
    fout << G.siz() << '\n';
    for (size_t i = 0; i < G.size(); i++)
    {
        for (size_t j = 0; j < G[i].size(); j++)
            fout << G[i][j] + 1 << ' ';
        fout << '\n';
    }
}

void Tarjan (const int n, const vector <int>* adj)
{
    idx[n] = lowlink[n] = index;
    index++;
    S.push(n), in_stack[n] = 1;

    vector <int> :: const iterator it;
    for (it = adj[n].begin(); it!=adj[n].end; ++it)
    {
        if (idx[*it] == -1) tarjan(*it, adj), lowlink[n] = min (lowlink[n], lowlink[*it]);
        else if (in_stack[*it]) lowlink[n] = min (lowlink[n], lowlink[*it]);
    }
    if (idx[n] == lowlink[n])
    {

    }
}

int main ()
{

}