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

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
const int NMAX = 100005;
vector<int> adj[NMAX];
bool vizitat[NMAX];
int N,M;
void dfs(int s) {
    vizitat[s] = true;
    for (int v : adj[s]) {
        if (!vizitat[v]) {
            dfs(v);
        }
    }
}
int main() {
    fin >> N >> M;
    int x,y;
    for (int i = 0; i < M; i++) {
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    int nrc = 0;
    for (int i = 1; i<=N; i++) {
        if (!vizitat[i]) {
            nrc++;
            dfs(i);
        }
    }
    fout << nrc;
    return 0;
}