#include <bits/stdc++.h>

using namespace std;

vector<int> adj[100005];

bool viz[100005];

void dfs(int i){
    viz[i] = 1;
    for(auto j : adj[i]){
        if(!viz[j]) dfs(j);
    }
}

int main(){
    
    ifstream cin("dfs.in");
    ofstream cout("dfs.out");
    
    int n, m;
    cin >> n >> m;
    for(int i = 1; i <= m; i++){
        int a, b;
        cin >> a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    
    int ans = 0;
    for(int i = 1; i <= n; i++){
        if(!viz[i]){
            ans++;
            dfs(i);
        }
    }
    cout << ans << '\n';
    
    return 0;
}