#include <fstream>
#include <vector>
using namespace std;

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

vector<int> g[100005];
bool viz[100005];

void dfs(int x) {
    viz[x] = true;
    for (int y : g[x])
        if (!viz[y])
            dfs(y);
}

int main() {
    int n, m;
    fin >> n >> m;
    for (int i = 0; i < m; i++) {
        int x, y;
        fin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }

    int nr = 0;
    for (int i = 1; i <= n; i++) {
        if (!viz[i]) {
            nr++;
            dfs(i);
        }
    }

    fout << nr << '\n';
}