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

using namespace std;

const int NMAX = 100003;

int seen[NMAX];
vector <int> v[NMAX];

void dfs(int k) {
    seen[k] = 1;

    for (auto node: v[k]) {
        if (!seen[node]) {
            dfs(node);
        }
    }
}

int main() {
    int n, m, a, b;

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

    cin >> n >> m;

    for (int i = 1; i <= m; i++) {
        cin >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    int sol = 0;

    for (int i = 1; i <= n; i++) {
        if (!seen[i]) {
            sol++;
            dfs(i);
        }
    }

    cout << sol;

    return 0;
}