#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");

vector<vector<int>> adj;
vector<bool> visited;

void dfs(int node){
    visited[node] =true;
    for(int neigh : adj[node]){
        if(!visited[neigh])
            dfs(neigh);
    }
}

int main(){
    int n,m;
    f >> n;
    f >> m;
    adj.resize(n + 1);       
    visited.resize(n + 1, false);
    for (int i = 0; i < m; ++i) {
        int x, y;
        f >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x); 
    }
    int c =0;
    for(int i=1;i<=n;i++){
        if(!visited[i]){
            dfs(i);
            c++;
        }
    }
    g << c;
    f.close();
    g.close();
}