#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

const int nmax = 100005;
vector<int> list_vec[nmax];
vector<int> viz;
int comp;

void dfs(int start)
{
    viz[start] = 1;
    for(auto i : list_vec[start])
    {
        if(!viz[i])
            dfs(i);
    }
}
int main()
{
    int n, m, u, v, i;
    fin>>n>>m;


    for(i = 1; i <= m; ++i)
    {
        fin>>u>>v;
        list_vec[u].push_back(v);
        list_vec[v].push_back(u);
    }

    viz.assign(n + 1, 0);

    for(i = 1; i <= n; ++i)
    {
        if(!viz[i])
        {
            ++comp;
            dfs(i);
        }
    }
    fout<<comp;
    return 0;
}