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

using namespace std;

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

const int MAXN = 100005;
vector<int> G[MAXN];
bool viz[MAXN];
int n, m;

void dfs(int u){
    viz[u] = true;

    for (int v : G[u]){
        if (!viz[v]){
            dfs(v);
        }
    }
}


int main(){
    fin >> n >> m;

    for (int i = 1; i <= m; i++){
        int u, v;
        fin >> u >> v;
        G[u].push_back(v);
        G[v].push_back(u);
    }

    int componente_conexe = 0;

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

    fout << componente_conexe;

    return 0;
}