#include <fstream>
#include <vector>

using namespace std;

int n;

void DFS(int nod, vector < vector<int> > &v, vector<int> &viz, int culoare){
    viz[nod] = culoare;
    for (auto y:v[nod]){
        if (viz[y] == -1){
            DFS(y, v, viz, culoare);
        }
    }
}

int main(){
    ifstream in("dfs.in");
    ofstream out("dfs.out");
    int m;
    in >> n >> m;
    vector < vector<int> > v(n+1);
    for (int i = 1; i <= m; i++){
        int x, y;
        in >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    vector <int> viz(n+1, -1);
    int culoare = 0;
    for (int i = 1; i <= n; i++){
        if (viz[i] == -1){
            culoare++;
            DFS(i, v, viz, culoare);
        }
    }
    out << culoare;
    in.close();
    out.close();
    return 0;
}