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

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

vector<int> visited;
vector<vector<int> > adj;
int n, m;

void DFS(int i) {
    visited[i] = 1;
    for (auto &vecin :adj[i]) {
        if (visited[vecin] == 0) {
            DFS(vecin);
        }
    }
}

int main() {
    fin >> n >> m;
    adj.resize(n);
    visited.resize(n);
    for (int i=0 ; i<m ; ++i) {
        int x, y;
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    int components = 0;
    for (int i=0 ; i<n ; ++i) {
        if (visited[i] == 0) {
            components++;
            DFS(i);
        }
    }
    fout << components;
}