#include <fstream>
#include <vector>
using namespace std;
fstream cin("dfs.in");
ofstream cout("dfs.out");
const int NMAX = 1e5  + 1;
vector <int> gr[NMAX];
int n, m, viz[NMAX];
void dfs(int nod) {
    viz[nod] = 1;
    for(unsigned i = 0; i < gr[nod].size(); ++i) {
        int fiu = gr[nod][i];
        if(viz[fiu] == 0) {
            dfs(fiu);
        }
    }
}
int main()
{
    cin >> n >> m;
    for(int i = 1; i <= m; ++i) {
        int x, y;
        cin >> x >> y;
        gr[x].push_back(y);
        gr[y].push_back(x);
    }
    int nc = 0;
    for(int i = 1; i <= n; ++i) {
        if(viz[i] == 0) {
            ++nc;
            dfs(i);
        }
    }
    cout << nc;
    return 0;
}