#include <fstream>
#include <vector>

using namespace std;

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

const int dim = 100005;

int n, m;
vector<vector<int>> g(dim);
vector<bool> viz(dim, false);

void dfs(int nod) {
    viz[nod] = true;

    for (const int& i : g[nod])
        if (!viz[i])
            dfs(i);
}

int main(){
    fin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int x, y;
        fin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    int c = 0;
    for (int i = 1; i <= n; i++) {
        if (!viz[i]) {
            c++;
            dfs(i);
        }
    }
    fout << c;
    return 0;
}