#include <fstream>
#include <vector>

using namespace std;

const int Nmax = 100005;

int n, m;
bool viz[Nmax];
vector<int> L[Nmax];

void dfs(int nod) {
    viz[nod] = true;
    for(int vec : L[nod]) {
        if(!viz[vec]) {
            dfs(vec);
        }
    }
}

int main() {
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");
    fin >> n >> m;
    for(int i = 1; i <= m; i++) {
        int x, y;
        fin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x);
    }

    int nr_comp = 0;
    for(int i = 1; i <= n; i++) {
        if(!viz[i]) {
            nr_comp++;
            dfs(i);
        }
    }

    fout << nr_comp;
    return 0;
}