#include <fstream>
#include <vector>

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");
const int NMAX=100001;
vector < int > Muchii[NMAX];
bool viz[NMAX];

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

int main()
{
    int n, m;
    int contor=0;
    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(!viz[i]) {
            contor++;
            DFS(i);
        }
    }
    fout<<contor;
    return 0;
}