#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
#define MAXIM 100005
bool vizitat[MAXIM];
unsigned int islands=0;
vector <int> muchii[MAXIM];

void dfs(int now)
{
    vizitat[now]=true;
    for(unsigned int i=0; i<muchii[now].size(); i++)
    {
        int next=muchii[now][i];
        if(!vizitat[next])
        {
            dfs(next);
        }
    }
}

void citire()
{
    int x, y, N, M;
    fin>>N>>M;
    for(int i=1; i<=M; i++)
    {
        fin>>x>>y;
        muchii[x].push_back(y);
        muchii[y].push_back(x);
    }
    for(int i=1; i<=N; i++)
    {
        if(!vizitat[i])
        {
            islands++;
            dfs(i);
        }
    }

}

int main()
{
    citire();
    fout<<islands<<"\n";
    return 0;
}