#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#define MAXN 100005
using namespace std;

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

int n,m, nr_c=0;

vector <int> G[MAXN];

int viz[MAXN];

void dfs(int nod)
{
    viz[nod]=1;
    for(auto &x:G[nod])
        if(!viz[x])
            dfs(x);
}

void citire()
{
    fin>>n>>m;
    int x,y;
    for(int i=0;i<m;i++)
        fin>>x>>y, G[x].push_back(y), G[y].push_back(x);
}

void componente_conexe()
{
    for(int i=1;i<=n;i++)
        if(!viz[i])
            nr_c++, dfs(i);
    fout<<nr_c;
}
int main()
{
    citire();
    componente_conexe();
    return 0;
}