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

#define NMAX 1000001

int visited[NMAX] = {0};

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

int main() {
    int n, m;
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);

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

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

    cout << cnt << '\n';

    return 0;
}