#include <fstream>
#include <vector>

using namespace std;

void dfs(int i, const vector<vector<int>>& graph, vector<int>& visited)
{
    visited[i] = 1;
    for (auto& v : graph[i])
    {
        if (!visited[v])
        {
            dfs(v, graph, visited);
        }
    }
}

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

    int n, m;
    fin >> n >> m;

    vector<vector<int>> graph(n + 1, vector<int>());

    for (int i = 0; i < m; ++i)
    {
        int u, v;
        fin >> u >> v;
        graph[u].push_back(v);
        graph[v].push_back(u);
    }

    vector<int> visited(n + 1, 0);
    int total_components = 0;

    for (int i = 1; i <= n; ++i)
    {
        if (!visited[i])
        {
            dfs(i, graph, visited);
            total_components++;
        }
    }

    fout << total_components << endl;

    return 0;
}