#include <fstream>
#include <vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

void dfs(int node, const vector<vector<int>>& adj, vector<bool>& visited) {
    visited[node] = true;
    for (int neighbor : adj[node]) {
        if (!visited[neighbor]) {
            dfs(neighbor, adj, visited);
        }
    }
}

int main() {
    int n, m, counter = 0;
    fin >> n >> m;
    vector<vector<int>> adj(n + 1);
    vector<bool> visited(n + 1, false);
    for (int i = 0; i < m; ++i) {
        int u, v;
        fin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }

    for (int i = 1; i <= n; ++i) {
        if (!visited[i]) {
            dfs(i, adj, visited);
            counter++;
        }
    }

    fout << counter;
    return 0;
}