#include <fstream>
#include <vector>
#include <string>



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

vector <int> L[100001];
int vis[100001];


void dfs(int node) {
    vis[node]= 1;
    for(auto vec : L[node]) {
        if(vis[vec]==0)
            dfs(vec) ;
    }
}
int main() {
    // implementarre dfs, numarare comp conexe

    int n,m;
    cin>>n>>m;
    for(int i=1;i<=m; ++i) {
        int x,y;
        cin>>x>>y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    int nr = 0;
    for(int i=1; i<=n; ++i) {
        if(vis[i] == 0){
            nr++;
            dfs(i);
        }
    }
    cout<<nr;
    return 0;
}