#include <fstream>
#include <vector>
using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

int N, M;
vector<vector<int>> adj;
vector<bool> visited;

void DFS(int node) {
    visited[node] = true;
    for (int neighbor : adj[node]) {
        if (!visited[neighbor]) {
            DFS(neighbor);
        }
    }
}

int main() {
    fin >> N >> M;
    adj.resize(N + 1);
    visited.resize(N + 1, false);

    for (int i = 0; i < M; ++i) {
        int X, Y;
        fin >> X >> Y;
        adj[X].push_back(Y);
        adj[Y].push_back(X);
    }

    int componentCount = 0;
    for (int i = 1; i <= N; ++i) {
        if (!visited[i]) {
            DFS(i);
            ++componentCount;
        }
    }

    fout << componentCount << endl;
    return 0;
}