#include <fstream>
#include <vector>

using namespace std;

/*ifstream cin ("input");
ofstream cout ("output");*/

ifstream cin ("dfs.in");
ofstream cout ("dfs.out");

vector < vector < int > > gr (100100);
vector < int > used (100100);

void dfs (int root){
    for (auto &x : gr[root]){
        if (!used[x]){
            used[x] = true;
            dfs(x);
        }
    }
}

int main() {

    ios::sync_with_stdio(false);
    cin.tie(NULL);

    int nodes , edges;
    cin>>nodes>>edges;

    for (int i=1; i<=edges; i++){
        int a , b;
        cin>>a>>b;
        gr[a].push_back(b);
        gr[b].push_back(a);
    }

    int cont = 0;

    for (int i=1; i<=nodes; i++){
        if (!used[i]){
            cont ++;
            used[i] = true;
            dfs(i);
        }
    }

    cout<<cont;

    return 0;
}