#include <fstream>
#include <vector>

using namespace std;

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

const int MAXN = 100005;

int n, m;
vector<int> adj[MAXN];
bool viz[MAXN];

void dfs(int nod) {
    viz[nod] = true;
    for (int vecin : adj[nod]) {
        if (!viz[vecin]) {
            dfs(vecin);
        }
    }
}

int main() {
    fin >> n >> m;
    for (int i= 0; i < m; ++i) {
        int u, v;
        fin >> u >>v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    int conexe = 0;
    for (int i = 1; i<=n; ++i) {
        if (!viz[i]) {
            conexe++;
            dfs(i);
        }
    }
    fout << conexe << "\n";
    return 0;
}