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

using namespace std;

// O(m)
void dfs(int node, vector<vector<int>>& edges, vector<bool>& viz) {
    viz[node] = true;

    // parcurg vecinii lui node
    for (int i = 0; i < edges[node].size(); i++) {
        int vecin = edges[node][i];
        if (!viz[vecin]) {
            dfs(vecin, edges, viz);
        }
    }
}

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

    int n, m; cin >> n >> m;
    vector<vector<int>> edges(n);
    for (int i = 0; i < m; i++) {
        int a, b; cin >> a >> b;
        a--; b--;
        edges[a].push_back(b);
        edges[b].push_back(a);
    }

    vector<bool> viz(n);
    int cnt = 0;
    for (int i = 0; i < n; i++) {
        if (!viz[i]) {
            cnt++;
            dfs(i, edges, viz);
        }
    }

    cout << cnt << "\n";

    return 0;
}