#include <fstream>
#include <vector>

using namespace std;

ifstream cin("dfs.in");
ofstream cout("dfs.out");

void dfs(int current_node, vector<vector<int>>& adj, vector<bool>& visited) {
    visited[current_node] = 1;

    for (int i = 0; i < adj[current_node].size(); ++i)
        if (!visited[adj[current_node][i]])
            dfs(adj[current_node][i], adj, visited);
}

int main() {
    int n, m;
    cin >> n >> m;

    vector<vector<int>> adj(n + 1);

    for (int i = 0; i < m; ++i) {
        int x, y;
        cin >> x >> y;

        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    vector<bool> visited(n + 1, false);

    int conexe = 0;
    for (int i = 1; i <= n; ++i)
        if (!visited[i]) {
            dfs(i, adj, visited);
            ++conexe;
        }

    cout << conexe << endl;
}