#include <vector>
#include <fstream>

#define NMAX 100010
using std::vector;

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

int n, m;
vector<int> ad[NMAX];

int nr;
bool vis[NMAX];

void dfs(int node) {
    vis[node] = true;
    for (int nghb : ad[node])
        if (!vis[nghb])
            dfs(nghb);
}

int main() {
    fin >> n >> m;
    for (int i = 0; i < m; i++) {
        int x, y;
        fin >> x >> y;

        ad[x].push_back(y);
        ad[y].push_back(x);
    }

    for (int i = 1; i <= n; i++)
        if (!vis[i]) {
            dfs(i);
            nr++;
        }
    fout << nr << '\n';

    fout.close();
    return 0;
}