#include <bits/stdc++.h>

using namespace std;

ifstream fin("dfs.in"); ofstream fout("dfs.out");
vector<vector<int>> graf;
vector<bool> vis;

void DFS(int node){
    if(vis[node]) return;
    vis[node] = true;
    for(auto adj : graf[node]){
        DFS(adj);
    }
}
int main(){
    int n, m;
    fin >> n >> m;
    graf.resize(n+1);
    vis.resize(n+1);
    for(int i = 1; i<=m; i++){
        int u, v; fin >> u >> v;
        graf[u].push_back(v);
        graf[v].push_back(u);
    }
    int k = 0;
    for(int i = 1; i<=n; i++){
        if(!vis[i]){
            k++;
            DFS(i);
        }
    }
    fout << k << endl;

}