#include <iostream>
#include <algorithm>
#include <cmath>
#include <set>
#include <vector>
#include <iomanip>
#include <cstdio>
using namespace std;

typedef long double ld;

const int N = 1e5;

vector <bool> used;
vector <int> v[N];

void dfs(int x)
{
    used[x] = true;
    for (int i = 0; i < v[x].size(); i++)
    {
        if (!used[v[x][i]])
            dfs(v[x][i]);
    }
}


int main() {
    ios::sync_with_stdio(0);
    int n, m, a, b;
    cin >> n >> m;

    for (int i = 0; i < m; i++)
    {
        cin >> a >> b;
        a--; b--;
        v[a].push_back(b);
    }

    for (int i = 0; i < n; i++) {
        if (!used[i])
            dfs(i);
    }
    return 0;
}