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

using namespace std;

ifstream f("dfs.in");
ofstream g("dfs.out");

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;
    int n,m,x,y;
    
    f>>n>>m;
    adj.resize(n+5);
    viz.resize(n+5);
    for(int i=1;i<=m;i++){
        f>>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++;
        }
    }
    g<<cnt<<'\n';


        
}