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

vector<int> L[100005];
bool viz[100005];
void dfs(int nod){
    // cout << nod << " ";
    viz[nod] = 1;
    for(int i=0;i<L[nod].size();i++){
        int vefin = L[nod][i];
        if(viz[vefin]==0){
            dfs(vefin);
        }
    }

}
int main() {
    int n, m;
    fin >> n >> m;
    for (int i = 0; i < m; i++) {
        int a,b;
        fin >> a >> b;
        L[a].push_back(b);
        L[b].push_back(a);
    }
    // dfs(1);
    int cc=0;
    for(int i=1;i<=n;i++){
        if(viz[i]==0){
            cc++;
            dfs(i);
        }
    }
    fout << cc;
    return 0;
}