#include <fstream>
#include <vector>

using namespace std;

const int Nmax = 100000;
vector <int> adj[Nmax + 1];
bool visited[Nmax + 1];

void dfs(int node)
{
    if (visited[node])
    {
        return;
    }
    visited[node] = true;
    for (auto u : adj[node])
    {
        dfs(u);
    }
}

int main()
{
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");
    int n, m;
    fin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        int u, v;
        fin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    int cnt = 0;
    for (int i = 1; i <= n; i++)
    {
        if (visited[i] == 0)
        {
            cnt++;
            dfs(i);
        }
    }
    fout << cnt;
    return 0;
}