#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

const int maxn = 1e5;
vector<int> adj[maxn + 1];
bool visited[maxn + 1];

void dfs(int node) {
    visited[node] = true;
    for (int child: adj[node])
        if (!visited[child])
            dfs(child);
}

int main() {
    int n, m;
    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 cnt = 0;
    for (int i = 1; i <= n; i++)
        if (!visited[i]) {
            cnt++;
            dfs(i);
        }
    fout << cnt << '\n';

    return 0;
}