/*
    Keep It Simple!
*/

#include <vector>
#include <fstream>
#include <queue>

using namespace std;

const int kMaxN = 100005;

int N,M,cnt;
vector<int> G[kMaxN];
bool used[kMaxN];

void DFS(int node) {
    used[node] = true;
    for (auto it:G[node])
        if(!used[it])
            DFS(it);
}

void Solve() {
    ifstream fin("dfs.in");
    fin >> N >> M;
    for (int i(1); i <= M; ++i) {
        int x,y;
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    fin.close();

    for (int i(1); i <= N; ++i) {
        if(!used[i]) {
            ++cnt;
            DFS(i);
        }
    }

    ofstream fout("dfs.out");
    fout << cnt << '\n';
    fout.close();
}

int main() {
    Solve();
    return 0;
}