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


long n,m;

ifstream f("dfs.in");
ofstream g("dfs.out");
vector <vector <int> > graf;
bool visited[100];

void Citire()
{
    int x,y;
    f>>n>>m;
    graf.resize(n);
    for (int i=0;i<m;i++)
    {
        f>>x>>y;
        x--;
        y--;
        graf[x].push_back(y);
        graf[y].push_back(x);
    }
}

void DFS (int x)
{
    if (x>n-1||x<0)
        return;
    //if (visited[x]==false)
        visited[x]=true;

    for (int i=0;i<graf[x].size();i++)
    {
        if (visited[graf[x][i]]==false)
            DFS(graf[x][i]);
    }
}



void CompConexe ()
{
    int counter=0;
    for (int i=0;i<n;i++)
    {
        if (visited[i]==false)
        {
            DFS(i);
            counter++;
        }
    }
    //cout<<counter<<" componente conexe";
    g<<counter;
    g.close();
}

int main ()
{
    Citire();
    CompConexe();
    return 0;
}