#include <iostream>
#include <fstream>


using namespace std;

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

int n,m;

vector<vector<int>>adj;
vector<int>viz;

void DFS(int nod){
    viz[nod]=1;
    for(int i : adj[nod]){
        if (viz[i] == 0)
            DFS(i);
    }
}

int main(){
    int cnt=0;
    fin>>n>>m;
    adj.resize(n+5);///a must altfel eroare la compilare - trebuie definit un size
    viz.resize(n+5);
    for(int i =1 ; i<=m ; i++){
        int x,y;
        fin>>x>>y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    for (int i =1; i<=n; i++){
        if (viz[i]==0){
            DFS(i);
            cnt++;
        }
    } 
    fout<<cnt;
    return 0;
}