#include <fstream>
#include <vector>

using namespace std;

void dfs(int nod, vector<int> G[], vector<bool> &v) {
    v[nod] = true;
    for(int i : G[nod]) {
        if(!v[i]) {
            dfs(i, G, v);
        }
    }
}

int main() {
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");
    int n, m;
    fin >> n >> m;
    vector<int> G[n + 2];
    vector<bool> v(n + 2, false);
    for(; m; --m) {
        int x, y;
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    int nrCompConex = 0;
    for(int i = 1; i <= n; ++i) {
        if(!v[i]) {
            ++nrCompConex;
            dfs(i, G, v);
        }
    }
    fout << nrCompConex << "\n";
    return 0;
}