#include <fstream>
#include <vector>
using namespace std;
ifstream cin("dfs.in");
ofstream cout("dfs.out");
int i, j, n, m, x, y, nr;
bool a[100002];
vector <int> L[100002];
void dfs(int nod){
    a[nod]=1;
    for(int i=0;i<L[nod].size();i++){
        if(a[L[nod][i]]==0)
            dfs(L[nod][i]);
    }

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


}