#include <fstream>
#include <vector>
#include <algorithm>
#define NMAX 100005
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n, m, nrc, i, j;
vector<int> g[NMAX];
bool viz[NMAX]; ///viz[i]=1 daca vf i a fost vizitat si 0 altfel
void citire();
void dfs(int x);
int main()
{
    citire();
    for (i=1; i<=n; i++)
        if(!viz[i])
    {
        nrc++; dfs(i);
    }
    fout<<nrc;
    return 0;
}
void citire()
{
    int k;
    fin>>n>>m;
    for (k=0; k<m; k++)
    {
        fin>>i>>j;
        g[i].push_back(j); g[j].push_back(i);
    }
}
void dfs(int x)
{
    int i;
    viz[x]=1;
    ///parcurg vecinii vf x
    for (i=0; i<g[x].size(); i++)
        if (!viz[g[x][i]]) dfs(g[x][i]);
}