#include <fstream>
#include <vector>

using namespace std;

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

const int NMAX = 1e5;
vector <int> graph[NMAX + 5];
bool viz[NMAX + 5];

void dfs(int node)
{
    viz[node] = 1;

    for(auto neigh : graph[node])
        if(viz[neigh] == 0)
            dfs(neigh);
}

int main()
{
    int n, m;
    fin >> n >> m;

    for(int i = 1; i <= m; i++)
    {
        int u, v;
        fin >> u >> v;

        graph[u].push_back(v);
        graph[v].push_back(u);
    }

    int comp_conex = 0;

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

    fout << comp_conex;

    fin.close();
    fout.close();
    return 0;
}