#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

vector<int> viz;
vector<vector<int>> vecini;
vector<pair<int, int>> dfsTree;

void dfs(int nod) {
    viz[nod] = 1;
    for (auto vecin : vecini[nod]) {
        if (viz[vecin] == 0) {
            dfsTree.push_back({nod, vecin});
            dfs(vecin);
        }
    }

}
int main() {

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

    int n, m;
    fin >> n >> m;

    viz.assign(n+1, 0);
    vecini.assign(n+1, {});

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

    int nrCompConexe = 0;
    
    for (int i = 1; i <= n; i++) {
        if (viz[i] == 0) {
            nrCompConexe ++;
            dfs(i);
        }
    }

    /*
    for (auto elem : dfsTree) {
        fout << "(" << elem.first << ", " <<  elem.second << ")" << endl; 
    }
    */
    fout << nrCompConexe;

    fin.close();
    fout.close();
    
    return 0;
}