#include <bits/stdc++.h>

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int nlim=100005;
int n, m, insule;
bool vizitat[nlim];
vector <int> Muchii[nlim];

void DFS(int Nod)
{
    vizitat[Nod]=true;
    for(unsigned int i=0; i< Muchii[Nod].size(); ++i)
    {
        int vecin=Muchii[Nod][i];
        if(!vizitat[vecin])
            DFS(vecin);
    }
}

void Citire()
{
    fin >> n >> m;
    for(int i=1; i<=m; ++i)
    {
        int x, y;
        fin >> x >> y;
        Muchii[x].push_back(y);
        Muchii[y].push_back(x);
    }
    for(int i=1; i<=n; ++i)
        if(!vizitat[i])
        {
            insule+=1;
            DFS(i);
        }
}

int main()
{
    Citire();
    fout << insule <<"\n";
    return 0;
}