#include <bits/stdc++.h>
using namespace std;

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

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

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m;
    fin >> n >> m;

    vector<vector<int>> adj(n + 1);
    for (int i = 0; i < m; ++i) {
        int x, y;
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    vector<bool> visited(n + 1, false);
    int ans = 0;

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

    fout << ans << "\n";

    return 0;
}