#include <fstream>
#include <vector>
#include <queue>
#include <stack>
using namespace std;


class graph{
int n,m;
vector<vector<int>> arcs;
public:
    graph(int n,int m,vector< vector<int>> arcs);
    void bfs(int start);
    void dfs(int start,vector<bool> &viz);
    void componente_conexe();
};

graph::graph(int n,int m,vector< vector<int>> arcs)
{
    this->n=n;
    this->m=m;
    this->arcs=arcs;
}
void graph::bfs(int start)
{
    queue<int> que;
    que.push(start);
    int *dist=new int[this->n];
    for(int i=0;i<n;i++)dist[i]=-1;//initializez distantele cu -1
    dist[start]=0;//distanta startului e 0
    while(!que.empty())//cat timp mai am in coada
    {
        int current=que.front();//iau elementul curent
        que.pop();//il scot din coada
        for(unsigned int i=0;i<arcs[current].size();i++)//ii parcurg lista de vecini
        {
            if(dist[arcs[current][i]]==-1)//daca vecinul e nevizitat
            {
                dist[arcs[current][i]]=dist[current]+1;//distanta lui devine cea a tatalui +1
                que.push(arcs[current][i]);//il pun in coada
            }
        }
    }
    ofstream fout("bfs.out");
    for(int i=0;i<this->n;i++)
        fout<<dist[i]<<' ';//afisez distantele
    delete[] dist;//sterg vectorul dinamic
}
void graph::dfs(int start,vector<bool> &viz)
{
    viz[start]=true;
        for(unsigned int i=0;i<arcs[start].size();i++)//ii parcurg lista de vecini
        {
            if(!viz[arcs[start][i]])//daca e nevizitat
            {
                viz[arcs[start][i]]=true;
                this->dfs(arcs[start][i],viz);//apelez recursiv dfs pe el
            }
        }
}
void graph::componente_conexe()
{
    vector<bool> viz(n);
    for(int i=0;i<n;i++)viz[i]=false;
    int componente=0;
    for(int i=0;i<n;i++)
        if(!viz[i])
        {
            dfs(i,viz);
            componente++;
        }
    ofstream fout("dfs.out");
    fout<<componente;

}
int main()
{
   /* int n,m,s;
    ifstream fin("bfs.in");
    fin>>n>>m>>s;
    s--;
    vector<vector<int>> arce(n);
    int a,b;
    for(int i=0;i<m;i++)
    {
        fin>>a>>b;
        a--;b--;
        arce[a].push_back(b);
    }
    graph g(n,m,arce);
    g.bfs(s);*/
    //^^bfs main
    int n,m;
    ifstream fin("dfs.in");
    fin>>n>>m;
    vector<vector<int>> arce(n);
    int a,b;
    for(int i=0;i<m;i++)
    {
        fin>>a>>b;
        a--;b--;
        arce[a].push_back(b);
    }
    graph g(n,m,arce);
    g.componente_conexe();
    return 0;
}